mirror of
https://github.com/sqlite/sqlite.git
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5d7aef16bf
CLI command. Renumber all of the bits in the bitmask used to enable various kinds of tracing, and add a trace bitmap decoder in sqliteInt.h. Changes to debugging logic only. No (intentional) changes to production code. FossilOrigin-Name: 8036445a36d9d982c1305935e7e37367bdf9e466b923eb6286b52524802e3ccd
3104 lines
104 KiB
C
3104 lines
104 KiB
C
/*
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** 2018 May 08
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**
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** The author disclaims copyright to this source code. In place of
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** a legal notice, here is a blessing:
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**
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** May you do good and not evil.
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** May you find forgiveness for yourself and forgive others.
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** May you share freely, never taking more than you give.
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**
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*************************************************************************
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*/
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#include "sqliteInt.h"
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#ifndef SQLITE_OMIT_WINDOWFUNC
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/*
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** SELECT REWRITING
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**
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** Any SELECT statement that contains one or more window functions in
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** either the select list or ORDER BY clause (the only two places window
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** functions may be used) is transformed by function sqlite3WindowRewrite()
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** in order to support window function processing. For example, with the
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** schema:
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**
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** CREATE TABLE t1(a, b, c, d, e, f, g);
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**
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** the statement:
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**
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** SELECT a+1, max(b) OVER (PARTITION BY c ORDER BY d) FROM t1 ORDER BY e;
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**
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** is transformed to:
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**
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** SELECT a+1, max(b) OVER (PARTITION BY c ORDER BY d) FROM (
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** SELECT a, e, c, d, b FROM t1 ORDER BY c, d
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** ) ORDER BY e;
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**
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** The flattening optimization is disabled when processing this transformed
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** SELECT statement. This allows the implementation of the window function
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** (in this case max()) to process rows sorted in order of (c, d), which
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** makes things easier for obvious reasons. More generally:
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**
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** * FROM, WHERE, GROUP BY and HAVING clauses are all moved to
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** the sub-query.
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**
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** * ORDER BY, LIMIT and OFFSET remain part of the parent query.
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**
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** * Terminals from each of the expression trees that make up the
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** select-list and ORDER BY expressions in the parent query are
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** selected by the sub-query. For the purposes of the transformation,
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** terminals are column references and aggregate functions.
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**
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** If there is more than one window function in the SELECT that uses
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** the same window declaration (the OVER bit), then a single scan may
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** be used to process more than one window function. For example:
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**
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** SELECT max(b) OVER (PARTITION BY c ORDER BY d),
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** min(e) OVER (PARTITION BY c ORDER BY d)
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** FROM t1;
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**
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** is transformed in the same way as the example above. However:
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**
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** SELECT max(b) OVER (PARTITION BY c ORDER BY d),
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** min(e) OVER (PARTITION BY a ORDER BY b)
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** FROM t1;
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**
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** Must be transformed to:
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**
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** SELECT max(b) OVER (PARTITION BY c ORDER BY d) FROM (
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** SELECT e, min(e) OVER (PARTITION BY a ORDER BY b), c, d, b FROM
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** SELECT a, e, c, d, b FROM t1 ORDER BY a, b
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** ) ORDER BY c, d
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** ) ORDER BY e;
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**
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** so that both min() and max() may process rows in the order defined by
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** their respective window declarations.
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**
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** INTERFACE WITH SELECT.C
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**
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** When processing the rewritten SELECT statement, code in select.c calls
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** sqlite3WhereBegin() to begin iterating through the results of the
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** sub-query, which is always implemented as a co-routine. It then calls
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** sqlite3WindowCodeStep() to process rows and finish the scan by calling
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** sqlite3WhereEnd().
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**
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** sqlite3WindowCodeStep() generates VM code so that, for each row returned
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** by the sub-query a sub-routine (OP_Gosub) coded by select.c is invoked.
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** When the sub-routine is invoked:
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**
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** * The results of all window-functions for the row are stored
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** in the associated Window.regResult registers.
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**
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** * The required terminal values are stored in the current row of
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** temp table Window.iEphCsr.
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**
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** In some cases, depending on the window frame and the specific window
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** functions invoked, sqlite3WindowCodeStep() caches each entire partition
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** in a temp table before returning any rows. In other cases it does not.
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** This detail is encapsulated within this file, the code generated by
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** select.c is the same in either case.
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**
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** BUILT-IN WINDOW FUNCTIONS
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**
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** This implementation features the following built-in window functions:
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**
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** row_number()
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** rank()
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** dense_rank()
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** percent_rank()
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** cume_dist()
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** ntile(N)
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** lead(expr [, offset [, default]])
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** lag(expr [, offset [, default]])
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** first_value(expr)
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** last_value(expr)
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** nth_value(expr, N)
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**
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** These are the same built-in window functions supported by Postgres.
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** Although the behaviour of aggregate window functions (functions that
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** can be used as either aggregates or window funtions) allows them to
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** be implemented using an API, built-in window functions are much more
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** esoteric. Additionally, some window functions (e.g. nth_value())
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** may only be implemented by caching the entire partition in memory.
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** As such, some built-in window functions use the same API as aggregate
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** window functions and some are implemented directly using VDBE
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** instructions. Additionally, for those functions that use the API, the
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** window frame is sometimes modified before the SELECT statement is
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** rewritten. For example, regardless of the specified window frame, the
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** row_number() function always uses:
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**
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** ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
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**
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** See sqlite3WindowUpdate() for details.
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**
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** As well as some of the built-in window functions, aggregate window
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** functions min() and max() are implemented using VDBE instructions if
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** the start of the window frame is declared as anything other than
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** UNBOUNDED PRECEDING.
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*/
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/*
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** Implementation of built-in window function row_number(). Assumes that the
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** window frame has been coerced to:
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**
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** ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
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*/
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static void row_numberStepFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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i64 *p = (i64*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ) (*p)++;
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UNUSED_PARAMETER(nArg);
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UNUSED_PARAMETER(apArg);
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}
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static void row_numberValueFunc(sqlite3_context *pCtx){
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i64 *p = (i64*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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sqlite3_result_int64(pCtx, (p ? *p : 0));
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}
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/*
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** Context object type used by rank(), dense_rank(), percent_rank() and
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** cume_dist().
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*/
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struct CallCount {
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i64 nValue;
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i64 nStep;
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i64 nTotal;
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};
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/*
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** Implementation of built-in window function dense_rank(). Assumes that
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** the window frame has been set to:
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**
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** RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
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*/
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static void dense_rankStepFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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struct CallCount *p;
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ) p->nStep = 1;
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UNUSED_PARAMETER(nArg);
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UNUSED_PARAMETER(apArg);
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}
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static void dense_rankValueFunc(sqlite3_context *pCtx){
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struct CallCount *p;
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ){
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if( p->nStep ){
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p->nValue++;
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p->nStep = 0;
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}
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sqlite3_result_int64(pCtx, p->nValue);
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}
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}
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/*
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** Implementation of built-in window function nth_value(). This
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** implementation is used in "slow mode" only - when the EXCLUDE clause
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** is not set to the default value "NO OTHERS".
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*/
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struct NthValueCtx {
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i64 nStep;
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sqlite3_value *pValue;
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};
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static void nth_valueStepFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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struct NthValueCtx *p;
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p = (struct NthValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ){
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i64 iVal;
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switch( sqlite3_value_numeric_type(apArg[1]) ){
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case SQLITE_INTEGER:
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iVal = sqlite3_value_int64(apArg[1]);
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break;
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case SQLITE_FLOAT: {
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double fVal = sqlite3_value_double(apArg[1]);
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if( ((i64)fVal)!=fVal ) goto error_out;
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iVal = (i64)fVal;
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break;
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}
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default:
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goto error_out;
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}
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if( iVal<=0 ) goto error_out;
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p->nStep++;
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if( iVal==p->nStep ){
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p->pValue = sqlite3_value_dup(apArg[0]);
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if( !p->pValue ){
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sqlite3_result_error_nomem(pCtx);
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}
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}
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}
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UNUSED_PARAMETER(nArg);
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UNUSED_PARAMETER(apArg);
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return;
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error_out:
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sqlite3_result_error(
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pCtx, "second argument to nth_value must be a positive integer", -1
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);
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}
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static void nth_valueFinalizeFunc(sqlite3_context *pCtx){
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struct NthValueCtx *p;
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p = (struct NthValueCtx*)sqlite3_aggregate_context(pCtx, 0);
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if( p && p->pValue ){
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sqlite3_result_value(pCtx, p->pValue);
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sqlite3_value_free(p->pValue);
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p->pValue = 0;
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}
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}
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#define nth_valueInvFunc noopStepFunc
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#define nth_valueValueFunc noopValueFunc
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static void first_valueStepFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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struct NthValueCtx *p;
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p = (struct NthValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p && p->pValue==0 ){
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p->pValue = sqlite3_value_dup(apArg[0]);
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if( !p->pValue ){
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sqlite3_result_error_nomem(pCtx);
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}
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}
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UNUSED_PARAMETER(nArg);
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UNUSED_PARAMETER(apArg);
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}
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static void first_valueFinalizeFunc(sqlite3_context *pCtx){
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struct NthValueCtx *p;
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p = (struct NthValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p && p->pValue ){
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sqlite3_result_value(pCtx, p->pValue);
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sqlite3_value_free(p->pValue);
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p->pValue = 0;
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}
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}
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#define first_valueInvFunc noopStepFunc
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#define first_valueValueFunc noopValueFunc
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/*
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** Implementation of built-in window function rank(). Assumes that
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** the window frame has been set to:
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**
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** RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
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*/
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static void rankStepFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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struct CallCount *p;
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ){
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p->nStep++;
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if( p->nValue==0 ){
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p->nValue = p->nStep;
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}
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}
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UNUSED_PARAMETER(nArg);
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UNUSED_PARAMETER(apArg);
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}
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static void rankValueFunc(sqlite3_context *pCtx){
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struct CallCount *p;
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ){
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sqlite3_result_int64(pCtx, p->nValue);
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p->nValue = 0;
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}
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}
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/*
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** Implementation of built-in window function percent_rank(). Assumes that
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** the window frame has been set to:
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**
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** GROUPS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
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*/
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static void percent_rankStepFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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struct CallCount *p;
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UNUSED_PARAMETER(nArg); assert( nArg==0 );
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UNUSED_PARAMETER(apArg);
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ){
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p->nTotal++;
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}
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}
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static void percent_rankInvFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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struct CallCount *p;
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UNUSED_PARAMETER(nArg); assert( nArg==0 );
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UNUSED_PARAMETER(apArg);
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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p->nStep++;
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}
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static void percent_rankValueFunc(sqlite3_context *pCtx){
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struct CallCount *p;
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ){
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p->nValue = p->nStep;
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if( p->nTotal>1 ){
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double r = (double)p->nValue / (double)(p->nTotal-1);
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sqlite3_result_double(pCtx, r);
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}else{
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sqlite3_result_double(pCtx, 0.0);
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}
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}
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}
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#define percent_rankFinalizeFunc percent_rankValueFunc
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|
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/*
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** Implementation of built-in window function cume_dist(). Assumes that
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** the window frame has been set to:
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**
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** GROUPS BETWEEN 1 FOLLOWING AND UNBOUNDED FOLLOWING
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*/
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static void cume_distStepFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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struct CallCount *p;
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UNUSED_PARAMETER(nArg); assert( nArg==0 );
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UNUSED_PARAMETER(apArg);
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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if( p ){
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p->nTotal++;
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}
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}
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static void cume_distInvFunc(
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sqlite3_context *pCtx,
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int nArg,
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sqlite3_value **apArg
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){
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struct CallCount *p;
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UNUSED_PARAMETER(nArg); assert( nArg==0 );
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UNUSED_PARAMETER(apArg);
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
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p->nStep++;
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}
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static void cume_distValueFunc(sqlite3_context *pCtx){
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struct CallCount *p;
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p = (struct CallCount*)sqlite3_aggregate_context(pCtx, 0);
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if( p ){
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double r = (double)(p->nStep) / (double)(p->nTotal);
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sqlite3_result_double(pCtx, r);
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}
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}
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#define cume_distFinalizeFunc cume_distValueFunc
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|
|
|
/*
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** Context object for ntile() window function.
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|
*/
|
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struct NtileCtx {
|
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i64 nTotal; /* Total rows in partition */
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|
i64 nParam; /* Parameter passed to ntile(N) */
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i64 iRow; /* Current row */
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};
|
|
|
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/*
|
|
** Implementation of ntile(). This assumes that the window frame has
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** been coerced to:
|
|
**
|
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** ROWS CURRENT ROW AND UNBOUNDED FOLLOWING
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|
*/
|
|
static void ntileStepFunc(
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|
sqlite3_context *pCtx,
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|
int nArg,
|
|
sqlite3_value **apArg
|
|
){
|
|
struct NtileCtx *p;
|
|
assert( nArg==1 ); UNUSED_PARAMETER(nArg);
|
|
p = (struct NtileCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
|
|
if( p ){
|
|
if( p->nTotal==0 ){
|
|
p->nParam = sqlite3_value_int64(apArg[0]);
|
|
if( p->nParam<=0 ){
|
|
sqlite3_result_error(
|
|
pCtx, "argument of ntile must be a positive integer", -1
|
|
);
|
|
}
|
|
}
|
|
p->nTotal++;
|
|
}
|
|
}
|
|
static void ntileInvFunc(
|
|
sqlite3_context *pCtx,
|
|
int nArg,
|
|
sqlite3_value **apArg
|
|
){
|
|
struct NtileCtx *p;
|
|
assert( nArg==1 ); UNUSED_PARAMETER(nArg);
|
|
UNUSED_PARAMETER(apArg);
|
|
p = (struct NtileCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
|
|
p->iRow++;
|
|
}
|
|
static void ntileValueFunc(sqlite3_context *pCtx){
|
|
struct NtileCtx *p;
|
|
p = (struct NtileCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
|
|
if( p && p->nParam>0 ){
|
|
int nSize = (p->nTotal / p->nParam);
|
|
if( nSize==0 ){
|
|
sqlite3_result_int64(pCtx, p->iRow+1);
|
|
}else{
|
|
i64 nLarge = p->nTotal - p->nParam*nSize;
|
|
i64 iSmall = nLarge*(nSize+1);
|
|
i64 iRow = p->iRow;
|
|
|
|
assert( (nLarge*(nSize+1) + (p->nParam-nLarge)*nSize)==p->nTotal );
|
|
|
|
if( iRow<iSmall ){
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sqlite3_result_int64(pCtx, 1 + iRow/(nSize+1));
|
|
}else{
|
|
sqlite3_result_int64(pCtx, 1 + nLarge + (iRow-iSmall)/nSize);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
#define ntileFinalizeFunc ntileValueFunc
|
|
|
|
/*
|
|
** Context object for last_value() window function.
|
|
*/
|
|
struct LastValueCtx {
|
|
sqlite3_value *pVal;
|
|
int nVal;
|
|
};
|
|
|
|
/*
|
|
** Implementation of last_value().
|
|
*/
|
|
static void last_valueStepFunc(
|
|
sqlite3_context *pCtx,
|
|
int nArg,
|
|
sqlite3_value **apArg
|
|
){
|
|
struct LastValueCtx *p;
|
|
UNUSED_PARAMETER(nArg);
|
|
p = (struct LastValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
|
|
if( p ){
|
|
sqlite3_value_free(p->pVal);
|
|
p->pVal = sqlite3_value_dup(apArg[0]);
|
|
if( p->pVal==0 ){
|
|
sqlite3_result_error_nomem(pCtx);
|
|
}else{
|
|
p->nVal++;
|
|
}
|
|
}
|
|
}
|
|
static void last_valueInvFunc(
|
|
sqlite3_context *pCtx,
|
|
int nArg,
|
|
sqlite3_value **apArg
|
|
){
|
|
struct LastValueCtx *p;
|
|
UNUSED_PARAMETER(nArg);
|
|
UNUSED_PARAMETER(apArg);
|
|
p = (struct LastValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
|
|
if( ALWAYS(p) ){
|
|
p->nVal--;
|
|
if( p->nVal==0 ){
|
|
sqlite3_value_free(p->pVal);
|
|
p->pVal = 0;
|
|
}
|
|
}
|
|
}
|
|
static void last_valueValueFunc(sqlite3_context *pCtx){
|
|
struct LastValueCtx *p;
|
|
p = (struct LastValueCtx*)sqlite3_aggregate_context(pCtx, 0);
|
|
if( p && p->pVal ){
|
|
sqlite3_result_value(pCtx, p->pVal);
|
|
}
|
|
}
|
|
static void last_valueFinalizeFunc(sqlite3_context *pCtx){
|
|
struct LastValueCtx *p;
|
|
p = (struct LastValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
|
|
if( p && p->pVal ){
|
|
sqlite3_result_value(pCtx, p->pVal);
|
|
sqlite3_value_free(p->pVal);
|
|
p->pVal = 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Static names for the built-in window function names. These static
|
|
** names are used, rather than string literals, so that FuncDef objects
|
|
** can be associated with a particular window function by direct
|
|
** comparison of the zName pointer. Example:
|
|
**
|
|
** if( pFuncDef->zName==row_valueName ){ ... }
|
|
*/
|
|
static const char row_numberName[] = "row_number";
|
|
static const char dense_rankName[] = "dense_rank";
|
|
static const char rankName[] = "rank";
|
|
static const char percent_rankName[] = "percent_rank";
|
|
static const char cume_distName[] = "cume_dist";
|
|
static const char ntileName[] = "ntile";
|
|
static const char last_valueName[] = "last_value";
|
|
static const char nth_valueName[] = "nth_value";
|
|
static const char first_valueName[] = "first_value";
|
|
static const char leadName[] = "lead";
|
|
static const char lagName[] = "lag";
|
|
|
|
/*
|
|
** No-op implementations of xStep() and xFinalize(). Used as place-holders
|
|
** for built-in window functions that never call those interfaces.
|
|
**
|
|
** The noopValueFunc() is called but is expected to do nothing. The
|
|
** noopStepFunc() is never called, and so it is marked with NO_TEST to
|
|
** let the test coverage routine know not to expect this function to be
|
|
** invoked.
|
|
*/
|
|
static void noopStepFunc( /*NO_TEST*/
|
|
sqlite3_context *p, /*NO_TEST*/
|
|
int n, /*NO_TEST*/
|
|
sqlite3_value **a /*NO_TEST*/
|
|
){ /*NO_TEST*/
|
|
UNUSED_PARAMETER(p); /*NO_TEST*/
|
|
UNUSED_PARAMETER(n); /*NO_TEST*/
|
|
UNUSED_PARAMETER(a); /*NO_TEST*/
|
|
assert(0); /*NO_TEST*/
|
|
} /*NO_TEST*/
|
|
static void noopValueFunc(sqlite3_context *p){ UNUSED_PARAMETER(p); /*no-op*/ }
|
|
|
|
/* Window functions that use all window interfaces: xStep, xFinal,
|
|
** xValue, and xInverse */
|
|
#define WINDOWFUNCALL(name,nArg,extra) { \
|
|
nArg, (SQLITE_FUNC_BUILTIN|SQLITE_UTF8|SQLITE_FUNC_WINDOW|extra), 0, 0, \
|
|
name ## StepFunc, name ## FinalizeFunc, name ## ValueFunc, \
|
|
name ## InvFunc, name ## Name, {0} \
|
|
}
|
|
|
|
/* Window functions that are implemented using bytecode and thus have
|
|
** no-op routines for their methods */
|
|
#define WINDOWFUNCNOOP(name,nArg,extra) { \
|
|
nArg, (SQLITE_FUNC_BUILTIN|SQLITE_UTF8|SQLITE_FUNC_WINDOW|extra), 0, 0, \
|
|
noopStepFunc, noopValueFunc, noopValueFunc, \
|
|
noopStepFunc, name ## Name, {0} \
|
|
}
|
|
|
|
/* Window functions that use all window interfaces: xStep, the
|
|
** same routine for xFinalize and xValue and which never call
|
|
** xInverse. */
|
|
#define WINDOWFUNCX(name,nArg,extra) { \
|
|
nArg, (SQLITE_FUNC_BUILTIN|SQLITE_UTF8|SQLITE_FUNC_WINDOW|extra), 0, 0, \
|
|
name ## StepFunc, name ## ValueFunc, name ## ValueFunc, \
|
|
noopStepFunc, name ## Name, {0} \
|
|
}
|
|
|
|
|
|
/*
|
|
** Register those built-in window functions that are not also aggregates.
|
|
*/
|
|
void sqlite3WindowFunctions(void){
|
|
static FuncDef aWindowFuncs[] = {
|
|
WINDOWFUNCX(row_number, 0, 0),
|
|
WINDOWFUNCX(dense_rank, 0, 0),
|
|
WINDOWFUNCX(rank, 0, 0),
|
|
WINDOWFUNCALL(percent_rank, 0, 0),
|
|
WINDOWFUNCALL(cume_dist, 0, 0),
|
|
WINDOWFUNCALL(ntile, 1, 0),
|
|
WINDOWFUNCALL(last_value, 1, 0),
|
|
WINDOWFUNCALL(nth_value, 2, 0),
|
|
WINDOWFUNCALL(first_value, 1, 0),
|
|
WINDOWFUNCNOOP(lead, 1, 0),
|
|
WINDOWFUNCNOOP(lead, 2, 0),
|
|
WINDOWFUNCNOOP(lead, 3, 0),
|
|
WINDOWFUNCNOOP(lag, 1, 0),
|
|
WINDOWFUNCNOOP(lag, 2, 0),
|
|
WINDOWFUNCNOOP(lag, 3, 0),
|
|
};
|
|
sqlite3InsertBuiltinFuncs(aWindowFuncs, ArraySize(aWindowFuncs));
|
|
}
|
|
|
|
static Window *windowFind(Parse *pParse, Window *pList, const char *zName){
|
|
Window *p;
|
|
for(p=pList; p; p=p->pNextWin){
|
|
if( sqlite3StrICmp(p->zName, zName)==0 ) break;
|
|
}
|
|
if( p==0 ){
|
|
sqlite3ErrorMsg(pParse, "no such window: %s", zName);
|
|
}
|
|
return p;
|
|
}
|
|
|
|
/*
|
|
** This function is called immediately after resolving the function name
|
|
** for a window function within a SELECT statement. Argument pList is a
|
|
** linked list of WINDOW definitions for the current SELECT statement.
|
|
** Argument pFunc is the function definition just resolved and pWin
|
|
** is the Window object representing the associated OVER clause. This
|
|
** function updates the contents of pWin as follows:
|
|
**
|
|
** * If the OVER clause refered to a named window (as in "max(x) OVER win"),
|
|
** search list pList for a matching WINDOW definition, and update pWin
|
|
** accordingly. If no such WINDOW clause can be found, leave an error
|
|
** in pParse.
|
|
**
|
|
** * If the function is a built-in window function that requires the
|
|
** window to be coerced (see "BUILT-IN WINDOW FUNCTIONS" at the top
|
|
** of this file), pWin is updated here.
|
|
*/
|
|
void sqlite3WindowUpdate(
|
|
Parse *pParse,
|
|
Window *pList, /* List of named windows for this SELECT */
|
|
Window *pWin, /* Window frame to update */
|
|
FuncDef *pFunc /* Window function definition */
|
|
){
|
|
if( pWin->zName && pWin->eFrmType==0 ){
|
|
Window *p = windowFind(pParse, pList, pWin->zName);
|
|
if( p==0 ) return;
|
|
pWin->pPartition = sqlite3ExprListDup(pParse->db, p->pPartition, 0);
|
|
pWin->pOrderBy = sqlite3ExprListDup(pParse->db, p->pOrderBy, 0);
|
|
pWin->pStart = sqlite3ExprDup(pParse->db, p->pStart, 0);
|
|
pWin->pEnd = sqlite3ExprDup(pParse->db, p->pEnd, 0);
|
|
pWin->eStart = p->eStart;
|
|
pWin->eEnd = p->eEnd;
|
|
pWin->eFrmType = p->eFrmType;
|
|
pWin->eExclude = p->eExclude;
|
|
}else{
|
|
sqlite3WindowChain(pParse, pWin, pList);
|
|
}
|
|
if( (pWin->eFrmType==TK_RANGE)
|
|
&& (pWin->pStart || pWin->pEnd)
|
|
&& (pWin->pOrderBy==0 || pWin->pOrderBy->nExpr!=1)
|
|
){
|
|
sqlite3ErrorMsg(pParse,
|
|
"RANGE with offset PRECEDING/FOLLOWING requires one ORDER BY expression"
|
|
);
|
|
}else
|
|
if( pFunc->funcFlags & SQLITE_FUNC_WINDOW ){
|
|
sqlite3 *db = pParse->db;
|
|
if( pWin->pFilter ){
|
|
sqlite3ErrorMsg(pParse,
|
|
"FILTER clause may only be used with aggregate window functions"
|
|
);
|
|
}else{
|
|
struct WindowUpdate {
|
|
const char *zFunc;
|
|
int eFrmType;
|
|
int eStart;
|
|
int eEnd;
|
|
} aUp[] = {
|
|
{ row_numberName, TK_ROWS, TK_UNBOUNDED, TK_CURRENT },
|
|
{ dense_rankName, TK_RANGE, TK_UNBOUNDED, TK_CURRENT },
|
|
{ rankName, TK_RANGE, TK_UNBOUNDED, TK_CURRENT },
|
|
{ percent_rankName, TK_GROUPS, TK_CURRENT, TK_UNBOUNDED },
|
|
{ cume_distName, TK_GROUPS, TK_FOLLOWING, TK_UNBOUNDED },
|
|
{ ntileName, TK_ROWS, TK_CURRENT, TK_UNBOUNDED },
|
|
{ leadName, TK_ROWS, TK_UNBOUNDED, TK_UNBOUNDED },
|
|
{ lagName, TK_ROWS, TK_UNBOUNDED, TK_CURRENT },
|
|
};
|
|
int i;
|
|
for(i=0; i<ArraySize(aUp); i++){
|
|
if( pFunc->zName==aUp[i].zFunc ){
|
|
sqlite3ExprDelete(db, pWin->pStart);
|
|
sqlite3ExprDelete(db, pWin->pEnd);
|
|
pWin->pEnd = pWin->pStart = 0;
|
|
pWin->eFrmType = aUp[i].eFrmType;
|
|
pWin->eStart = aUp[i].eStart;
|
|
pWin->eEnd = aUp[i].eEnd;
|
|
pWin->eExclude = 0;
|
|
if( pWin->eStart==TK_FOLLOWING ){
|
|
pWin->pStart = sqlite3Expr(db, TK_INTEGER, "1");
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
pWin->pWFunc = pFunc;
|
|
}
|
|
|
|
/*
|
|
** Context object passed through sqlite3WalkExprList() to
|
|
** selectWindowRewriteExprCb() by selectWindowRewriteEList().
|
|
*/
|
|
typedef struct WindowRewrite WindowRewrite;
|
|
struct WindowRewrite {
|
|
Window *pWin;
|
|
SrcList *pSrc;
|
|
ExprList *pSub;
|
|
Table *pTab;
|
|
Select *pSubSelect; /* Current sub-select, if any */
|
|
};
|
|
|
|
/*
|
|
** Callback function used by selectWindowRewriteEList(). If necessary,
|
|
** this function appends to the output expression-list and updates
|
|
** expression (*ppExpr) in place.
|
|
*/
|
|
static int selectWindowRewriteExprCb(Walker *pWalker, Expr *pExpr){
|
|
struct WindowRewrite *p = pWalker->u.pRewrite;
|
|
Parse *pParse = pWalker->pParse;
|
|
assert( p!=0 );
|
|
assert( p->pWin!=0 );
|
|
|
|
/* If this function is being called from within a scalar sub-select
|
|
** that used by the SELECT statement being processed, only process
|
|
** TK_COLUMN expressions that refer to it (the outer SELECT). Do
|
|
** not process aggregates or window functions at all, as they belong
|
|
** to the scalar sub-select. */
|
|
if( p->pSubSelect ){
|
|
if( pExpr->op!=TK_COLUMN ){
|
|
return WRC_Continue;
|
|
}else{
|
|
int nSrc = p->pSrc->nSrc;
|
|
int i;
|
|
for(i=0; i<nSrc; i++){
|
|
if( pExpr->iTable==p->pSrc->a[i].iCursor ) break;
|
|
}
|
|
if( i==nSrc ) return WRC_Continue;
|
|
}
|
|
}
|
|
|
|
switch( pExpr->op ){
|
|
|
|
case TK_FUNCTION:
|
|
if( !ExprHasProperty(pExpr, EP_WinFunc) ){
|
|
break;
|
|
}else{
|
|
Window *pWin;
|
|
for(pWin=p->pWin; pWin; pWin=pWin->pNextWin){
|
|
if( pExpr->y.pWin==pWin ){
|
|
assert( pWin->pOwner==pExpr );
|
|
return WRC_Prune;
|
|
}
|
|
}
|
|
}
|
|
/* no break */ deliberate_fall_through
|
|
|
|
case TK_AGG_FUNCTION:
|
|
case TK_COLUMN: {
|
|
int iCol = -1;
|
|
if( pParse->db->mallocFailed ) return WRC_Abort;
|
|
if( p->pSub ){
|
|
int i;
|
|
for(i=0; i<p->pSub->nExpr; i++){
|
|
if( 0==sqlite3ExprCompare(0, p->pSub->a[i].pExpr, pExpr, -1) ){
|
|
iCol = i;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if( iCol<0 ){
|
|
Expr *pDup = sqlite3ExprDup(pParse->db, pExpr, 0);
|
|
if( pDup && pDup->op==TK_AGG_FUNCTION ) pDup->op = TK_FUNCTION;
|
|
p->pSub = sqlite3ExprListAppend(pParse, p->pSub, pDup);
|
|
}
|
|
if( p->pSub ){
|
|
int f = pExpr->flags & EP_Collate;
|
|
assert( ExprHasProperty(pExpr, EP_Static)==0 );
|
|
ExprSetProperty(pExpr, EP_Static);
|
|
sqlite3ExprDelete(pParse->db, pExpr);
|
|
ExprClearProperty(pExpr, EP_Static);
|
|
memset(pExpr, 0, sizeof(Expr));
|
|
|
|
pExpr->op = TK_COLUMN;
|
|
pExpr->iColumn = (iCol<0 ? p->pSub->nExpr-1: iCol);
|
|
pExpr->iTable = p->pWin->iEphCsr;
|
|
pExpr->y.pTab = p->pTab;
|
|
pExpr->flags = f;
|
|
}
|
|
if( pParse->db->mallocFailed ) return WRC_Abort;
|
|
break;
|
|
}
|
|
|
|
default: /* no-op */
|
|
break;
|
|
}
|
|
|
|
return WRC_Continue;
|
|
}
|
|
static int selectWindowRewriteSelectCb(Walker *pWalker, Select *pSelect){
|
|
struct WindowRewrite *p = pWalker->u.pRewrite;
|
|
Select *pSave = p->pSubSelect;
|
|
if( pSave==pSelect ){
|
|
return WRC_Continue;
|
|
}else{
|
|
p->pSubSelect = pSelect;
|
|
sqlite3WalkSelect(pWalker, pSelect);
|
|
p->pSubSelect = pSave;
|
|
}
|
|
return WRC_Prune;
|
|
}
|
|
|
|
|
|
/*
|
|
** Iterate through each expression in expression-list pEList. For each:
|
|
**
|
|
** * TK_COLUMN,
|
|
** * aggregate function, or
|
|
** * window function with a Window object that is not a member of the
|
|
** Window list passed as the second argument (pWin).
|
|
**
|
|
** Append the node to output expression-list (*ppSub). And replace it
|
|
** with a TK_COLUMN that reads the (N-1)th element of table
|
|
** pWin->iEphCsr, where N is the number of elements in (*ppSub) after
|
|
** appending the new one.
|
|
*/
|
|
static void selectWindowRewriteEList(
|
|
Parse *pParse,
|
|
Window *pWin,
|
|
SrcList *pSrc,
|
|
ExprList *pEList, /* Rewrite expressions in this list */
|
|
Table *pTab,
|
|
ExprList **ppSub /* IN/OUT: Sub-select expression-list */
|
|
){
|
|
Walker sWalker;
|
|
WindowRewrite sRewrite;
|
|
|
|
assert( pWin!=0 );
|
|
memset(&sWalker, 0, sizeof(Walker));
|
|
memset(&sRewrite, 0, sizeof(WindowRewrite));
|
|
|
|
sRewrite.pSub = *ppSub;
|
|
sRewrite.pWin = pWin;
|
|
sRewrite.pSrc = pSrc;
|
|
sRewrite.pTab = pTab;
|
|
|
|
sWalker.pParse = pParse;
|
|
sWalker.xExprCallback = selectWindowRewriteExprCb;
|
|
sWalker.xSelectCallback = selectWindowRewriteSelectCb;
|
|
sWalker.u.pRewrite = &sRewrite;
|
|
|
|
(void)sqlite3WalkExprList(&sWalker, pEList);
|
|
|
|
*ppSub = sRewrite.pSub;
|
|
}
|
|
|
|
/*
|
|
** Append a copy of each expression in expression-list pAppend to
|
|
** expression list pList. Return a pointer to the result list.
|
|
*/
|
|
static ExprList *exprListAppendList(
|
|
Parse *pParse, /* Parsing context */
|
|
ExprList *pList, /* List to which to append. Might be NULL */
|
|
ExprList *pAppend, /* List of values to append. Might be NULL */
|
|
int bIntToNull
|
|
){
|
|
if( pAppend ){
|
|
int i;
|
|
int nInit = pList ? pList->nExpr : 0;
|
|
for(i=0; i<pAppend->nExpr; i++){
|
|
sqlite3 *db = pParse->db;
|
|
Expr *pDup = sqlite3ExprDup(db, pAppend->a[i].pExpr, 0);
|
|
if( db->mallocFailed ){
|
|
sqlite3ExprDelete(db, pDup);
|
|
break;
|
|
}
|
|
if( bIntToNull ){
|
|
int iDummy;
|
|
Expr *pSub;
|
|
pSub = sqlite3ExprSkipCollateAndLikely(pDup);
|
|
if( sqlite3ExprIsInteger(pSub, &iDummy) ){
|
|
pSub->op = TK_NULL;
|
|
pSub->flags &= ~(EP_IntValue|EP_IsTrue|EP_IsFalse);
|
|
pSub->u.zToken = 0;
|
|
}
|
|
}
|
|
pList = sqlite3ExprListAppend(pParse, pList, pDup);
|
|
if( pList ) pList->a[nInit+i].fg.sortFlags = pAppend->a[i].fg.sortFlags;
|
|
}
|
|
}
|
|
return pList;
|
|
}
|
|
|
|
/*
|
|
** When rewriting a query, if the new subquery in the FROM clause
|
|
** contains TK_AGG_FUNCTION nodes that refer to an outer query,
|
|
** then we have to increase the Expr->op2 values of those nodes
|
|
** due to the extra subquery layer that was added.
|
|
**
|
|
** See also the incrAggDepth() routine in resolve.c
|
|
*/
|
|
static int sqlite3WindowExtraAggFuncDepth(Walker *pWalker, Expr *pExpr){
|
|
if( pExpr->op==TK_AGG_FUNCTION
|
|
&& pExpr->op2>=pWalker->walkerDepth
|
|
){
|
|
pExpr->op2++;
|
|
}
|
|
return WRC_Continue;
|
|
}
|
|
|
|
static int disallowAggregatesInOrderByCb(Walker *pWalker, Expr *pExpr){
|
|
if( pExpr->op==TK_AGG_FUNCTION && pExpr->pAggInfo==0 ){
|
|
assert( !ExprHasProperty(pExpr, EP_IntValue) );
|
|
sqlite3ErrorMsg(pWalker->pParse,
|
|
"misuse of aggregate: %s()", pExpr->u.zToken);
|
|
}
|
|
return WRC_Continue;
|
|
}
|
|
|
|
/*
|
|
** If the SELECT statement passed as the second argument does not invoke
|
|
** any SQL window functions, this function is a no-op. Otherwise, it
|
|
** rewrites the SELECT statement so that window function xStep functions
|
|
** are invoked in the correct order as described under "SELECT REWRITING"
|
|
** at the top of this file.
|
|
*/
|
|
int sqlite3WindowRewrite(Parse *pParse, Select *p){
|
|
int rc = SQLITE_OK;
|
|
if( p->pWin
|
|
&& p->pPrior==0
|
|
&& ALWAYS((p->selFlags & SF_WinRewrite)==0)
|
|
&& ALWAYS(!IN_RENAME_OBJECT)
|
|
){
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
sqlite3 *db = pParse->db;
|
|
Select *pSub = 0; /* The subquery */
|
|
SrcList *pSrc = p->pSrc;
|
|
Expr *pWhere = p->pWhere;
|
|
ExprList *pGroupBy = p->pGroupBy;
|
|
Expr *pHaving = p->pHaving;
|
|
ExprList *pSort = 0;
|
|
|
|
ExprList *pSublist = 0; /* Expression list for sub-query */
|
|
Window *pMWin = p->pWin; /* Main window object */
|
|
Window *pWin; /* Window object iterator */
|
|
Table *pTab;
|
|
Walker w;
|
|
|
|
u32 selFlags = p->selFlags;
|
|
|
|
pTab = sqlite3DbMallocZero(db, sizeof(Table));
|
|
if( pTab==0 ){
|
|
return sqlite3ErrorToParser(db, SQLITE_NOMEM);
|
|
}
|
|
sqlite3AggInfoPersistWalkerInit(&w, pParse);
|
|
sqlite3WalkSelect(&w, p);
|
|
if( (p->selFlags & SF_Aggregate)==0 ){
|
|
w.xExprCallback = disallowAggregatesInOrderByCb;
|
|
w.xSelectCallback = 0;
|
|
sqlite3WalkExprList(&w, p->pOrderBy);
|
|
}
|
|
|
|
p->pSrc = 0;
|
|
p->pWhere = 0;
|
|
p->pGroupBy = 0;
|
|
p->pHaving = 0;
|
|
p->selFlags &= ~SF_Aggregate;
|
|
p->selFlags |= SF_WinRewrite;
|
|
|
|
/* Create the ORDER BY clause for the sub-select. This is the concatenation
|
|
** of the window PARTITION and ORDER BY clauses. Then, if this makes it
|
|
** redundant, remove the ORDER BY from the parent SELECT. */
|
|
pSort = exprListAppendList(pParse, 0, pMWin->pPartition, 1);
|
|
pSort = exprListAppendList(pParse, pSort, pMWin->pOrderBy, 1);
|
|
if( pSort && p->pOrderBy && p->pOrderBy->nExpr<=pSort->nExpr ){
|
|
int nSave = pSort->nExpr;
|
|
pSort->nExpr = p->pOrderBy->nExpr;
|
|
if( sqlite3ExprListCompare(pSort, p->pOrderBy, -1)==0 ){
|
|
sqlite3ExprListDelete(db, p->pOrderBy);
|
|
p->pOrderBy = 0;
|
|
}
|
|
pSort->nExpr = nSave;
|
|
}
|
|
|
|
/* Assign a cursor number for the ephemeral table used to buffer rows.
|
|
** The OpenEphemeral instruction is coded later, after it is known how
|
|
** many columns the table will have. */
|
|
pMWin->iEphCsr = pParse->nTab++;
|
|
pParse->nTab += 3;
|
|
|
|
selectWindowRewriteEList(pParse, pMWin, pSrc, p->pEList, pTab, &pSublist);
|
|
selectWindowRewriteEList(pParse, pMWin, pSrc, p->pOrderBy, pTab, &pSublist);
|
|
pMWin->nBufferCol = (pSublist ? pSublist->nExpr : 0);
|
|
|
|
/* Append the PARTITION BY and ORDER BY expressions to the to the
|
|
** sub-select expression list. They are required to figure out where
|
|
** boundaries for partitions and sets of peer rows lie. */
|
|
pSublist = exprListAppendList(pParse, pSublist, pMWin->pPartition, 0);
|
|
pSublist = exprListAppendList(pParse, pSublist, pMWin->pOrderBy, 0);
|
|
|
|
/* Append the arguments passed to each window function to the
|
|
** sub-select expression list. Also allocate two registers for each
|
|
** window function - one for the accumulator, another for interim
|
|
** results. */
|
|
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
|
|
ExprList *pArgs;
|
|
assert( ExprUseXList(pWin->pOwner) );
|
|
assert( pWin->pWFunc!=0 );
|
|
pArgs = pWin->pOwner->x.pList;
|
|
if( pWin->pWFunc->funcFlags & SQLITE_FUNC_SUBTYPE ){
|
|
selectWindowRewriteEList(pParse, pMWin, pSrc, pArgs, pTab, &pSublist);
|
|
pWin->iArgCol = (pSublist ? pSublist->nExpr : 0);
|
|
pWin->bExprArgs = 1;
|
|
}else{
|
|
pWin->iArgCol = (pSublist ? pSublist->nExpr : 0);
|
|
pSublist = exprListAppendList(pParse, pSublist, pArgs, 0);
|
|
}
|
|
if( pWin->pFilter ){
|
|
Expr *pFilter = sqlite3ExprDup(db, pWin->pFilter, 0);
|
|
pSublist = sqlite3ExprListAppend(pParse, pSublist, pFilter);
|
|
}
|
|
pWin->regAccum = ++pParse->nMem;
|
|
pWin->regResult = ++pParse->nMem;
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regAccum);
|
|
}
|
|
|
|
/* If there is no ORDER BY or PARTITION BY clause, and the window
|
|
** function accepts zero arguments, and there are no other columns
|
|
** selected (e.g. "SELECT row_number() OVER () FROM t1"), it is possible
|
|
** that pSublist is still NULL here. Add a constant expression here to
|
|
** keep everything legal in this case.
|
|
*/
|
|
if( pSublist==0 ){
|
|
pSublist = sqlite3ExprListAppend(pParse, 0,
|
|
sqlite3Expr(db, TK_INTEGER, "0")
|
|
);
|
|
}
|
|
|
|
pSub = sqlite3SelectNew(
|
|
pParse, pSublist, pSrc, pWhere, pGroupBy, pHaving, pSort, 0, 0
|
|
);
|
|
TREETRACE(0x40,pParse,pSub,
|
|
("New window-function subquery in FROM clause of (%u/%p)\n",
|
|
p->selId, p));
|
|
p->pSrc = sqlite3SrcListAppend(pParse, 0, 0, 0);
|
|
assert( pSub!=0 || p->pSrc==0 ); /* Due to db->mallocFailed test inside
|
|
** of sqlite3DbMallocRawNN() called from
|
|
** sqlite3SrcListAppend() */
|
|
if( p->pSrc ){
|
|
Table *pTab2;
|
|
p->pSrc->a[0].pSelect = pSub;
|
|
sqlite3SrcListAssignCursors(pParse, p->pSrc);
|
|
pSub->selFlags |= SF_Expanded|SF_OrderByReqd;
|
|
pTab2 = sqlite3ResultSetOfSelect(pParse, pSub, SQLITE_AFF_NONE);
|
|
pSub->selFlags |= (selFlags & SF_Aggregate);
|
|
if( pTab2==0 ){
|
|
/* Might actually be some other kind of error, but in that case
|
|
** pParse->nErr will be set, so if SQLITE_NOMEM is set, we will get
|
|
** the correct error message regardless. */
|
|
rc = SQLITE_NOMEM;
|
|
}else{
|
|
memcpy(pTab, pTab2, sizeof(Table));
|
|
pTab->tabFlags |= TF_Ephemeral;
|
|
p->pSrc->a[0].pTab = pTab;
|
|
pTab = pTab2;
|
|
memset(&w, 0, sizeof(w));
|
|
w.xExprCallback = sqlite3WindowExtraAggFuncDepth;
|
|
w.xSelectCallback = sqlite3WalkerDepthIncrease;
|
|
w.xSelectCallback2 = sqlite3WalkerDepthDecrease;
|
|
sqlite3WalkSelect(&w, pSub);
|
|
}
|
|
}else{
|
|
sqlite3SelectDelete(db, pSub);
|
|
}
|
|
if( db->mallocFailed ) rc = SQLITE_NOMEM;
|
|
|
|
/* Defer deleting the temporary table pTab because if an error occurred,
|
|
** there could still be references to that table embedded in the
|
|
** result-set or ORDER BY clause of the SELECT statement p. */
|
|
sqlite3ParserAddCleanup(pParse, sqlite3DbFree, pTab);
|
|
}
|
|
|
|
assert( rc==SQLITE_OK || pParse->nErr!=0 );
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
** Unlink the Window object from the Select to which it is attached,
|
|
** if it is attached.
|
|
*/
|
|
void sqlite3WindowUnlinkFromSelect(Window *p){
|
|
if( p->ppThis ){
|
|
*p->ppThis = p->pNextWin;
|
|
if( p->pNextWin ) p->pNextWin->ppThis = p->ppThis;
|
|
p->ppThis = 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Free the Window object passed as the second argument.
|
|
*/
|
|
void sqlite3WindowDelete(sqlite3 *db, Window *p){
|
|
if( p ){
|
|
sqlite3WindowUnlinkFromSelect(p);
|
|
sqlite3ExprDelete(db, p->pFilter);
|
|
sqlite3ExprListDelete(db, p->pPartition);
|
|
sqlite3ExprListDelete(db, p->pOrderBy);
|
|
sqlite3ExprDelete(db, p->pEnd);
|
|
sqlite3ExprDelete(db, p->pStart);
|
|
sqlite3DbFree(db, p->zName);
|
|
sqlite3DbFree(db, p->zBase);
|
|
sqlite3DbFree(db, p);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Free the linked list of Window objects starting at the second argument.
|
|
*/
|
|
void sqlite3WindowListDelete(sqlite3 *db, Window *p){
|
|
while( p ){
|
|
Window *pNext = p->pNextWin;
|
|
sqlite3WindowDelete(db, p);
|
|
p = pNext;
|
|
}
|
|
}
|
|
|
|
/*
|
|
** The argument expression is an PRECEDING or FOLLOWING offset. The
|
|
** value should be a non-negative integer. If the value is not a
|
|
** constant, change it to NULL. The fact that it is then a non-negative
|
|
** integer will be caught later. But it is important not to leave
|
|
** variable values in the expression tree.
|
|
*/
|
|
static Expr *sqlite3WindowOffsetExpr(Parse *pParse, Expr *pExpr){
|
|
if( 0==sqlite3ExprIsConstant(pExpr) ){
|
|
if( IN_RENAME_OBJECT ) sqlite3RenameExprUnmap(pParse, pExpr);
|
|
sqlite3ExprDelete(pParse->db, pExpr);
|
|
pExpr = sqlite3ExprAlloc(pParse->db, TK_NULL, 0, 0);
|
|
}
|
|
return pExpr;
|
|
}
|
|
|
|
/*
|
|
** Allocate and return a new Window object describing a Window Definition.
|
|
*/
|
|
Window *sqlite3WindowAlloc(
|
|
Parse *pParse, /* Parsing context */
|
|
int eType, /* Frame type. TK_RANGE, TK_ROWS, TK_GROUPS, or 0 */
|
|
int eStart, /* Start type: CURRENT, PRECEDING, FOLLOWING, UNBOUNDED */
|
|
Expr *pStart, /* Start window size if TK_PRECEDING or FOLLOWING */
|
|
int eEnd, /* End type: CURRENT, FOLLOWING, TK_UNBOUNDED, PRECEDING */
|
|
Expr *pEnd, /* End window size if TK_FOLLOWING or PRECEDING */
|
|
u8 eExclude /* EXCLUDE clause */
|
|
){
|
|
Window *pWin = 0;
|
|
int bImplicitFrame = 0;
|
|
|
|
/* Parser assures the following: */
|
|
assert( eType==0 || eType==TK_RANGE || eType==TK_ROWS || eType==TK_GROUPS );
|
|
assert( eStart==TK_CURRENT || eStart==TK_PRECEDING
|
|
|| eStart==TK_UNBOUNDED || eStart==TK_FOLLOWING );
|
|
assert( eEnd==TK_CURRENT || eEnd==TK_FOLLOWING
|
|
|| eEnd==TK_UNBOUNDED || eEnd==TK_PRECEDING );
|
|
assert( (eStart==TK_PRECEDING || eStart==TK_FOLLOWING)==(pStart!=0) );
|
|
assert( (eEnd==TK_FOLLOWING || eEnd==TK_PRECEDING)==(pEnd!=0) );
|
|
|
|
if( eType==0 ){
|
|
bImplicitFrame = 1;
|
|
eType = TK_RANGE;
|
|
}
|
|
|
|
/* Additionally, the
|
|
** starting boundary type may not occur earlier in the following list than
|
|
** the ending boundary type:
|
|
**
|
|
** UNBOUNDED PRECEDING
|
|
** <expr> PRECEDING
|
|
** CURRENT ROW
|
|
** <expr> FOLLOWING
|
|
** UNBOUNDED FOLLOWING
|
|
**
|
|
** The parser ensures that "UNBOUNDED PRECEDING" cannot be used as an ending
|
|
** boundary, and than "UNBOUNDED FOLLOWING" cannot be used as a starting
|
|
** frame boundary.
|
|
*/
|
|
if( (eStart==TK_CURRENT && eEnd==TK_PRECEDING)
|
|
|| (eStart==TK_FOLLOWING && (eEnd==TK_PRECEDING || eEnd==TK_CURRENT))
|
|
){
|
|
sqlite3ErrorMsg(pParse, "unsupported frame specification");
|
|
goto windowAllocErr;
|
|
}
|
|
|
|
pWin = (Window*)sqlite3DbMallocZero(pParse->db, sizeof(Window));
|
|
if( pWin==0 ) goto windowAllocErr;
|
|
pWin->eFrmType = eType;
|
|
pWin->eStart = eStart;
|
|
pWin->eEnd = eEnd;
|
|
if( eExclude==0 && OptimizationDisabled(pParse->db, SQLITE_WindowFunc) ){
|
|
eExclude = TK_NO;
|
|
}
|
|
pWin->eExclude = eExclude;
|
|
pWin->bImplicitFrame = bImplicitFrame;
|
|
pWin->pEnd = sqlite3WindowOffsetExpr(pParse, pEnd);
|
|
pWin->pStart = sqlite3WindowOffsetExpr(pParse, pStart);
|
|
return pWin;
|
|
|
|
windowAllocErr:
|
|
sqlite3ExprDelete(pParse->db, pEnd);
|
|
sqlite3ExprDelete(pParse->db, pStart);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
** Attach PARTITION and ORDER BY clauses pPartition and pOrderBy to window
|
|
** pWin. Also, if parameter pBase is not NULL, set pWin->zBase to the
|
|
** equivalent nul-terminated string.
|
|
*/
|
|
Window *sqlite3WindowAssemble(
|
|
Parse *pParse,
|
|
Window *pWin,
|
|
ExprList *pPartition,
|
|
ExprList *pOrderBy,
|
|
Token *pBase
|
|
){
|
|
if( pWin ){
|
|
pWin->pPartition = pPartition;
|
|
pWin->pOrderBy = pOrderBy;
|
|
if( pBase ){
|
|
pWin->zBase = sqlite3DbStrNDup(pParse->db, pBase->z, pBase->n);
|
|
}
|
|
}else{
|
|
sqlite3ExprListDelete(pParse->db, pPartition);
|
|
sqlite3ExprListDelete(pParse->db, pOrderBy);
|
|
}
|
|
return pWin;
|
|
}
|
|
|
|
/*
|
|
** Window *pWin has just been created from a WINDOW clause. Tokne pBase
|
|
** is the base window. Earlier windows from the same WINDOW clause are
|
|
** stored in the linked list starting at pWin->pNextWin. This function
|
|
** either updates *pWin according to the base specification, or else
|
|
** leaves an error in pParse.
|
|
*/
|
|
void sqlite3WindowChain(Parse *pParse, Window *pWin, Window *pList){
|
|
if( pWin->zBase ){
|
|
sqlite3 *db = pParse->db;
|
|
Window *pExist = windowFind(pParse, pList, pWin->zBase);
|
|
if( pExist ){
|
|
const char *zErr = 0;
|
|
/* Check for errors */
|
|
if( pWin->pPartition ){
|
|
zErr = "PARTITION clause";
|
|
}else if( pExist->pOrderBy && pWin->pOrderBy ){
|
|
zErr = "ORDER BY clause";
|
|
}else if( pExist->bImplicitFrame==0 ){
|
|
zErr = "frame specification";
|
|
}
|
|
if( zErr ){
|
|
sqlite3ErrorMsg(pParse,
|
|
"cannot override %s of window: %s", zErr, pWin->zBase
|
|
);
|
|
}else{
|
|
pWin->pPartition = sqlite3ExprListDup(db, pExist->pPartition, 0);
|
|
if( pExist->pOrderBy ){
|
|
assert( pWin->pOrderBy==0 );
|
|
pWin->pOrderBy = sqlite3ExprListDup(db, pExist->pOrderBy, 0);
|
|
}
|
|
sqlite3DbFree(db, pWin->zBase);
|
|
pWin->zBase = 0;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Attach window object pWin to expression p.
|
|
*/
|
|
void sqlite3WindowAttach(Parse *pParse, Expr *p, Window *pWin){
|
|
if( p ){
|
|
assert( p->op==TK_FUNCTION );
|
|
assert( pWin );
|
|
p->y.pWin = pWin;
|
|
ExprSetProperty(p, EP_WinFunc);
|
|
pWin->pOwner = p;
|
|
if( (p->flags & EP_Distinct) && pWin->eFrmType!=TK_FILTER ){
|
|
sqlite3ErrorMsg(pParse,
|
|
"DISTINCT is not supported for window functions"
|
|
);
|
|
}
|
|
}else{
|
|
sqlite3WindowDelete(pParse->db, pWin);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Possibly link window pWin into the list at pSel->pWin (window functions
|
|
** to be processed as part of SELECT statement pSel). The window is linked
|
|
** in if either (a) there are no other windows already linked to this
|
|
** SELECT, or (b) the windows already linked use a compatible window frame.
|
|
*/
|
|
void sqlite3WindowLink(Select *pSel, Window *pWin){
|
|
if( pSel ){
|
|
if( 0==pSel->pWin || 0==sqlite3WindowCompare(0, pSel->pWin, pWin, 0) ){
|
|
pWin->pNextWin = pSel->pWin;
|
|
if( pSel->pWin ){
|
|
pSel->pWin->ppThis = &pWin->pNextWin;
|
|
}
|
|
pSel->pWin = pWin;
|
|
pWin->ppThis = &pSel->pWin;
|
|
}else{
|
|
if( sqlite3ExprListCompare(pWin->pPartition, pSel->pWin->pPartition,-1) ){
|
|
pSel->selFlags |= SF_MultiPart;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Return 0 if the two window objects are identical, 1 if they are
|
|
** different, or 2 if it cannot be determined if the objects are identical
|
|
** or not. Identical window objects can be processed in a single scan.
|
|
*/
|
|
int sqlite3WindowCompare(
|
|
const Parse *pParse,
|
|
const Window *p1,
|
|
const Window *p2,
|
|
int bFilter
|
|
){
|
|
int res;
|
|
if( NEVER(p1==0) || NEVER(p2==0) ) return 1;
|
|
if( p1->eFrmType!=p2->eFrmType ) return 1;
|
|
if( p1->eStart!=p2->eStart ) return 1;
|
|
if( p1->eEnd!=p2->eEnd ) return 1;
|
|
if( p1->eExclude!=p2->eExclude ) return 1;
|
|
if( sqlite3ExprCompare(pParse, p1->pStart, p2->pStart, -1) ) return 1;
|
|
if( sqlite3ExprCompare(pParse, p1->pEnd, p2->pEnd, -1) ) return 1;
|
|
if( (res = sqlite3ExprListCompare(p1->pPartition, p2->pPartition, -1)) ){
|
|
return res;
|
|
}
|
|
if( (res = sqlite3ExprListCompare(p1->pOrderBy, p2->pOrderBy, -1)) ){
|
|
return res;
|
|
}
|
|
if( bFilter ){
|
|
if( (res = sqlite3ExprCompare(pParse, p1->pFilter, p2->pFilter, -1)) ){
|
|
return res;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
** This is called by code in select.c before it calls sqlite3WhereBegin()
|
|
** to begin iterating through the sub-query results. It is used to allocate
|
|
** and initialize registers and cursors used by sqlite3WindowCodeStep().
|
|
*/
|
|
void sqlite3WindowCodeInit(Parse *pParse, Select *pSelect){
|
|
int nEphExpr = pSelect->pSrc->a[0].pSelect->pEList->nExpr;
|
|
Window *pMWin = pSelect->pWin;
|
|
Window *pWin;
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
|
|
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pMWin->iEphCsr, nEphExpr);
|
|
sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->iEphCsr+1, pMWin->iEphCsr);
|
|
sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->iEphCsr+2, pMWin->iEphCsr);
|
|
sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->iEphCsr+3, pMWin->iEphCsr);
|
|
|
|
/* Allocate registers to use for PARTITION BY values, if any. Initialize
|
|
** said registers to NULL. */
|
|
if( pMWin->pPartition ){
|
|
int nExpr = pMWin->pPartition->nExpr;
|
|
pMWin->regPart = pParse->nMem+1;
|
|
pParse->nMem += nExpr;
|
|
sqlite3VdbeAddOp3(v, OP_Null, 0, pMWin->regPart, pMWin->regPart+nExpr-1);
|
|
}
|
|
|
|
pMWin->regOne = ++pParse->nMem;
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, pMWin->regOne);
|
|
|
|
if( pMWin->eExclude ){
|
|
pMWin->regStartRowid = ++pParse->nMem;
|
|
pMWin->regEndRowid = ++pParse->nMem;
|
|
pMWin->csrApp = pParse->nTab++;
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, pMWin->regStartRowid);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, pMWin->regEndRowid);
|
|
sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->csrApp, pMWin->iEphCsr);
|
|
return;
|
|
}
|
|
|
|
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
|
|
FuncDef *p = pWin->pWFunc;
|
|
if( (p->funcFlags & SQLITE_FUNC_MINMAX) && pWin->eStart!=TK_UNBOUNDED ){
|
|
/* The inline versions of min() and max() require a single ephemeral
|
|
** table and 3 registers. The registers are used as follows:
|
|
**
|
|
** regApp+0: slot to copy min()/max() argument to for MakeRecord
|
|
** regApp+1: integer value used to ensure keys are unique
|
|
** regApp+2: output of MakeRecord
|
|
*/
|
|
ExprList *pList;
|
|
KeyInfo *pKeyInfo;
|
|
assert( ExprUseXList(pWin->pOwner) );
|
|
pList = pWin->pOwner->x.pList;
|
|
pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pList, 0, 0);
|
|
pWin->csrApp = pParse->nTab++;
|
|
pWin->regApp = pParse->nMem+1;
|
|
pParse->nMem += 3;
|
|
if( pKeyInfo && pWin->pWFunc->zName[1]=='i' ){
|
|
assert( pKeyInfo->aSortFlags[0]==0 );
|
|
pKeyInfo->aSortFlags[0] = KEYINFO_ORDER_DESC;
|
|
}
|
|
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pWin->csrApp, 2);
|
|
sqlite3VdbeAppendP4(v, pKeyInfo, P4_KEYINFO);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, pWin->regApp+1);
|
|
}
|
|
else if( p->zName==nth_valueName || p->zName==first_valueName ){
|
|
/* Allocate two registers at pWin->regApp. These will be used to
|
|
** store the start and end index of the current frame. */
|
|
pWin->regApp = pParse->nMem+1;
|
|
pWin->csrApp = pParse->nTab++;
|
|
pParse->nMem += 2;
|
|
sqlite3VdbeAddOp2(v, OP_OpenDup, pWin->csrApp, pMWin->iEphCsr);
|
|
}
|
|
else if( p->zName==leadName || p->zName==lagName ){
|
|
pWin->csrApp = pParse->nTab++;
|
|
sqlite3VdbeAddOp2(v, OP_OpenDup, pWin->csrApp, pMWin->iEphCsr);
|
|
}
|
|
}
|
|
}
|
|
|
|
#define WINDOW_STARTING_INT 0
|
|
#define WINDOW_ENDING_INT 1
|
|
#define WINDOW_NTH_VALUE_INT 2
|
|
#define WINDOW_STARTING_NUM 3
|
|
#define WINDOW_ENDING_NUM 4
|
|
|
|
/*
|
|
** A "PRECEDING <expr>" (eCond==0) or "FOLLOWING <expr>" (eCond==1) or the
|
|
** value of the second argument to nth_value() (eCond==2) has just been
|
|
** evaluated and the result left in register reg. This function generates VM
|
|
** code to check that the value is a non-negative integer and throws an
|
|
** exception if it is not.
|
|
*/
|
|
static void windowCheckValue(Parse *pParse, int reg, int eCond){
|
|
static const char *azErr[] = {
|
|
"frame starting offset must be a non-negative integer",
|
|
"frame ending offset must be a non-negative integer",
|
|
"second argument to nth_value must be a positive integer",
|
|
"frame starting offset must be a non-negative number",
|
|
"frame ending offset must be a non-negative number",
|
|
};
|
|
static int aOp[] = { OP_Ge, OP_Ge, OP_Gt, OP_Ge, OP_Ge };
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
int regZero = sqlite3GetTempReg(pParse);
|
|
assert( eCond>=0 && eCond<ArraySize(azErr) );
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, regZero);
|
|
if( eCond>=WINDOW_STARTING_NUM ){
|
|
int regString = sqlite3GetTempReg(pParse);
|
|
sqlite3VdbeAddOp4(v, OP_String8, 0, regString, 0, "", P4_STATIC);
|
|
sqlite3VdbeAddOp3(v, OP_Ge, regString, sqlite3VdbeCurrentAddr(v)+2, reg);
|
|
sqlite3VdbeChangeP5(v, SQLITE_AFF_NUMERIC|SQLITE_JUMPIFNULL);
|
|
VdbeCoverage(v);
|
|
assert( eCond==3 || eCond==4 );
|
|
VdbeCoverageIf(v, eCond==3);
|
|
VdbeCoverageIf(v, eCond==4);
|
|
}else{
|
|
sqlite3VdbeAddOp2(v, OP_MustBeInt, reg, sqlite3VdbeCurrentAddr(v)+2);
|
|
VdbeCoverage(v);
|
|
assert( eCond==0 || eCond==1 || eCond==2 );
|
|
VdbeCoverageIf(v, eCond==0);
|
|
VdbeCoverageIf(v, eCond==1);
|
|
VdbeCoverageIf(v, eCond==2);
|
|
}
|
|
sqlite3VdbeAddOp3(v, aOp[eCond], regZero, sqlite3VdbeCurrentAddr(v)+2, reg);
|
|
sqlite3VdbeChangeP5(v, SQLITE_AFF_NUMERIC);
|
|
VdbeCoverageNeverNullIf(v, eCond==0); /* NULL case captured by */
|
|
VdbeCoverageNeverNullIf(v, eCond==1); /* the OP_MustBeInt */
|
|
VdbeCoverageNeverNullIf(v, eCond==2);
|
|
VdbeCoverageNeverNullIf(v, eCond==3); /* NULL case caught by */
|
|
VdbeCoverageNeverNullIf(v, eCond==4); /* the OP_Ge */
|
|
sqlite3MayAbort(pParse);
|
|
sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_ERROR, OE_Abort);
|
|
sqlite3VdbeAppendP4(v, (void*)azErr[eCond], P4_STATIC);
|
|
sqlite3ReleaseTempReg(pParse, regZero);
|
|
}
|
|
|
|
/*
|
|
** Return the number of arguments passed to the window-function associated
|
|
** with the object passed as the only argument to this function.
|
|
*/
|
|
static int windowArgCount(Window *pWin){
|
|
const ExprList *pList;
|
|
assert( ExprUseXList(pWin->pOwner) );
|
|
pList = pWin->pOwner->x.pList;
|
|
return (pList ? pList->nExpr : 0);
|
|
}
|
|
|
|
typedef struct WindowCodeArg WindowCodeArg;
|
|
typedef struct WindowCsrAndReg WindowCsrAndReg;
|
|
|
|
/*
|
|
** See comments above struct WindowCodeArg.
|
|
*/
|
|
struct WindowCsrAndReg {
|
|
int csr; /* Cursor number */
|
|
int reg; /* First in array of peer values */
|
|
};
|
|
|
|
/*
|
|
** A single instance of this structure is allocated on the stack by
|
|
** sqlite3WindowCodeStep() and a pointer to it passed to the various helper
|
|
** routines. This is to reduce the number of arguments required by each
|
|
** helper function.
|
|
**
|
|
** regArg:
|
|
** Each window function requires an accumulator register (just as an
|
|
** ordinary aggregate function does). This variable is set to the first
|
|
** in an array of accumulator registers - one for each window function
|
|
** in the WindowCodeArg.pMWin list.
|
|
**
|
|
** eDelete:
|
|
** The window functions implementation sometimes caches the input rows
|
|
** that it processes in a temporary table. If it is not zero, this
|
|
** variable indicates when rows may be removed from the temp table (in
|
|
** order to reduce memory requirements - it would always be safe just
|
|
** to leave them there). Possible values for eDelete are:
|
|
**
|
|
** WINDOW_RETURN_ROW:
|
|
** An input row can be discarded after it is returned to the caller.
|
|
**
|
|
** WINDOW_AGGINVERSE:
|
|
** An input row can be discarded after the window functions xInverse()
|
|
** callbacks have been invoked in it.
|
|
**
|
|
** WINDOW_AGGSTEP:
|
|
** An input row can be discarded after the window functions xStep()
|
|
** callbacks have been invoked in it.
|
|
**
|
|
** start,current,end
|
|
** Consider a window-frame similar to the following:
|
|
**
|
|
** (ORDER BY a, b GROUPS BETWEEN 2 PRECEDING AND 2 FOLLOWING)
|
|
**
|
|
** The windows functions implmentation caches the input rows in a temp
|
|
** table, sorted by "a, b" (it actually populates the cache lazily, and
|
|
** aggressively removes rows once they are no longer required, but that's
|
|
** a mere detail). It keeps three cursors open on the temp table. One
|
|
** (current) that points to the next row to return to the query engine
|
|
** once its window function values have been calculated. Another (end)
|
|
** points to the next row to call the xStep() method of each window function
|
|
** on (so that it is 2 groups ahead of current). And a third (start) that
|
|
** points to the next row to call the xInverse() method of each window
|
|
** function on.
|
|
**
|
|
** Each cursor (start, current and end) consists of a VDBE cursor
|
|
** (WindowCsrAndReg.csr) and an array of registers (starting at
|
|
** WindowCodeArg.reg) that always contains a copy of the peer values
|
|
** read from the corresponding cursor.
|
|
**
|
|
** Depending on the window-frame in question, all three cursors may not
|
|
** be required. In this case both WindowCodeArg.csr and reg are set to
|
|
** 0.
|
|
*/
|
|
struct WindowCodeArg {
|
|
Parse *pParse; /* Parse context */
|
|
Window *pMWin; /* First in list of functions being processed */
|
|
Vdbe *pVdbe; /* VDBE object */
|
|
int addrGosub; /* OP_Gosub to this address to return one row */
|
|
int regGosub; /* Register used with OP_Gosub(addrGosub) */
|
|
int regArg; /* First in array of accumulator registers */
|
|
int eDelete; /* See above */
|
|
int regRowid;
|
|
|
|
WindowCsrAndReg start;
|
|
WindowCsrAndReg current;
|
|
WindowCsrAndReg end;
|
|
};
|
|
|
|
/*
|
|
** Generate VM code to read the window frames peer values from cursor csr into
|
|
** an array of registers starting at reg.
|
|
*/
|
|
static void windowReadPeerValues(
|
|
WindowCodeArg *p,
|
|
int csr,
|
|
int reg
|
|
){
|
|
Window *pMWin = p->pMWin;
|
|
ExprList *pOrderBy = pMWin->pOrderBy;
|
|
if( pOrderBy ){
|
|
Vdbe *v = sqlite3GetVdbe(p->pParse);
|
|
ExprList *pPart = pMWin->pPartition;
|
|
int iColOff = pMWin->nBufferCol + (pPart ? pPart->nExpr : 0);
|
|
int i;
|
|
for(i=0; i<pOrderBy->nExpr; i++){
|
|
sqlite3VdbeAddOp3(v, OP_Column, csr, iColOff+i, reg+i);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Generate VM code to invoke either xStep() (if bInverse is 0) or
|
|
** xInverse (if bInverse is non-zero) for each window function in the
|
|
** linked list starting at pMWin. Or, for built-in window functions
|
|
** that do not use the standard function API, generate the required
|
|
** inline VM code.
|
|
**
|
|
** If argument csr is greater than or equal to 0, then argument reg is
|
|
** the first register in an array of registers guaranteed to be large
|
|
** enough to hold the array of arguments for each function. In this case
|
|
** the arguments are extracted from the current row of csr into the
|
|
** array of registers before invoking OP_AggStep or OP_AggInverse
|
|
**
|
|
** Or, if csr is less than zero, then the array of registers at reg is
|
|
** already populated with all columns from the current row of the sub-query.
|
|
**
|
|
** If argument regPartSize is non-zero, then it is a register containing the
|
|
** number of rows in the current partition.
|
|
*/
|
|
static void windowAggStep(
|
|
WindowCodeArg *p,
|
|
Window *pMWin, /* Linked list of window functions */
|
|
int csr, /* Read arguments from this cursor */
|
|
int bInverse, /* True to invoke xInverse instead of xStep */
|
|
int reg /* Array of registers */
|
|
){
|
|
Parse *pParse = p->pParse;
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
Window *pWin;
|
|
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
|
|
FuncDef *pFunc = pWin->pWFunc;
|
|
int regArg;
|
|
int nArg = pWin->bExprArgs ? 0 : windowArgCount(pWin);
|
|
int i;
|
|
|
|
assert( bInverse==0 || pWin->eStart!=TK_UNBOUNDED );
|
|
|
|
/* All OVER clauses in the same window function aggregate step must
|
|
** be the same. */
|
|
assert( pWin==pMWin || sqlite3WindowCompare(pParse,pWin,pMWin,0)!=1 );
|
|
|
|
for(i=0; i<nArg; i++){
|
|
if( i!=1 || pFunc->zName!=nth_valueName ){
|
|
sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol+i, reg+i);
|
|
}else{
|
|
sqlite3VdbeAddOp3(v, OP_Column, pMWin->iEphCsr, pWin->iArgCol+i, reg+i);
|
|
}
|
|
}
|
|
regArg = reg;
|
|
|
|
if( pMWin->regStartRowid==0
|
|
&& (pFunc->funcFlags & SQLITE_FUNC_MINMAX)
|
|
&& (pWin->eStart!=TK_UNBOUNDED)
|
|
){
|
|
int addrIsNull = sqlite3VdbeAddOp1(v, OP_IsNull, regArg);
|
|
VdbeCoverage(v);
|
|
if( bInverse==0 ){
|
|
sqlite3VdbeAddOp2(v, OP_AddImm, pWin->regApp+1, 1);
|
|
sqlite3VdbeAddOp2(v, OP_SCopy, regArg, pWin->regApp);
|
|
sqlite3VdbeAddOp3(v, OP_MakeRecord, pWin->regApp, 2, pWin->regApp+2);
|
|
sqlite3VdbeAddOp2(v, OP_IdxInsert, pWin->csrApp, pWin->regApp+2);
|
|
}else{
|
|
sqlite3VdbeAddOp4Int(v, OP_SeekGE, pWin->csrApp, 0, regArg, 1);
|
|
VdbeCoverageNeverTaken(v);
|
|
sqlite3VdbeAddOp1(v, OP_Delete, pWin->csrApp);
|
|
sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);
|
|
}
|
|
sqlite3VdbeJumpHere(v, addrIsNull);
|
|
}else if( pWin->regApp ){
|
|
assert( pFunc->zName==nth_valueName
|
|
|| pFunc->zName==first_valueName
|
|
);
|
|
assert( bInverse==0 || bInverse==1 );
|
|
sqlite3VdbeAddOp2(v, OP_AddImm, pWin->regApp+1-bInverse, 1);
|
|
}else if( pFunc->xSFunc!=noopStepFunc ){
|
|
int addrIf = 0;
|
|
if( pWin->pFilter ){
|
|
int regTmp;
|
|
assert( ExprUseXList(pWin->pOwner) );
|
|
assert( pWin->bExprArgs || !nArg ||nArg==pWin->pOwner->x.pList->nExpr );
|
|
assert( pWin->bExprArgs || nArg ||pWin->pOwner->x.pList==0 );
|
|
regTmp = sqlite3GetTempReg(pParse);
|
|
sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol+nArg,regTmp);
|
|
addrIf = sqlite3VdbeAddOp3(v, OP_IfNot, regTmp, 0, 1);
|
|
VdbeCoverage(v);
|
|
sqlite3ReleaseTempReg(pParse, regTmp);
|
|
}
|
|
|
|
if( pWin->bExprArgs ){
|
|
int iOp = sqlite3VdbeCurrentAddr(v);
|
|
int iEnd;
|
|
|
|
assert( ExprUseXList(pWin->pOwner) );
|
|
nArg = pWin->pOwner->x.pList->nExpr;
|
|
regArg = sqlite3GetTempRange(pParse, nArg);
|
|
sqlite3ExprCodeExprList(pParse, pWin->pOwner->x.pList, regArg, 0, 0);
|
|
|
|
for(iEnd=sqlite3VdbeCurrentAddr(v); iOp<iEnd; iOp++){
|
|
VdbeOp *pOp = sqlite3VdbeGetOp(v, iOp);
|
|
if( pOp->opcode==OP_Column && pOp->p1==pMWin->iEphCsr ){
|
|
pOp->p1 = csr;
|
|
}
|
|
}
|
|
}
|
|
if( pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){
|
|
CollSeq *pColl;
|
|
assert( nArg>0 );
|
|
assert( ExprUseXList(pWin->pOwner) );
|
|
pColl = sqlite3ExprNNCollSeq(pParse, pWin->pOwner->x.pList->a[0].pExpr);
|
|
sqlite3VdbeAddOp4(v, OP_CollSeq, 0,0,0, (const char*)pColl, P4_COLLSEQ);
|
|
}
|
|
sqlite3VdbeAddOp3(v, bInverse? OP_AggInverse : OP_AggStep,
|
|
bInverse, regArg, pWin->regAccum);
|
|
sqlite3VdbeAppendP4(v, pFunc, P4_FUNCDEF);
|
|
sqlite3VdbeChangeP5(v, (u8)nArg);
|
|
if( pWin->bExprArgs ){
|
|
sqlite3ReleaseTempRange(pParse, regArg, nArg);
|
|
}
|
|
if( addrIf ) sqlite3VdbeJumpHere(v, addrIf);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Values that may be passed as the second argument to windowCodeOp().
|
|
*/
|
|
#define WINDOW_RETURN_ROW 1
|
|
#define WINDOW_AGGINVERSE 2
|
|
#define WINDOW_AGGSTEP 3
|
|
|
|
/*
|
|
** Generate VM code to invoke either xValue() (bFin==0) or xFinalize()
|
|
** (bFin==1) for each window function in the linked list starting at
|
|
** pMWin. Or, for built-in window-functions that do not use the standard
|
|
** API, generate the equivalent VM code.
|
|
*/
|
|
static void windowAggFinal(WindowCodeArg *p, int bFin){
|
|
Parse *pParse = p->pParse;
|
|
Window *pMWin = p->pMWin;
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
Window *pWin;
|
|
|
|
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
|
|
if( pMWin->regStartRowid==0
|
|
&& (pWin->pWFunc->funcFlags & SQLITE_FUNC_MINMAX)
|
|
&& (pWin->eStart!=TK_UNBOUNDED)
|
|
){
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regResult);
|
|
sqlite3VdbeAddOp1(v, OP_Last, pWin->csrApp);
|
|
VdbeCoverage(v);
|
|
sqlite3VdbeAddOp3(v, OP_Column, pWin->csrApp, 0, pWin->regResult);
|
|
sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);
|
|
}else if( pWin->regApp ){
|
|
assert( pMWin->regStartRowid==0 );
|
|
}else{
|
|
int nArg = windowArgCount(pWin);
|
|
if( bFin ){
|
|
sqlite3VdbeAddOp2(v, OP_AggFinal, pWin->regAccum, nArg);
|
|
sqlite3VdbeAppendP4(v, pWin->pWFunc, P4_FUNCDEF);
|
|
sqlite3VdbeAddOp2(v, OP_Copy, pWin->regAccum, pWin->regResult);
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regAccum);
|
|
}else{
|
|
sqlite3VdbeAddOp3(v, OP_AggValue,pWin->regAccum,nArg,pWin->regResult);
|
|
sqlite3VdbeAppendP4(v, pWin->pWFunc, P4_FUNCDEF);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Generate code to calculate the current values of all window functions in the
|
|
** p->pMWin list by doing a full scan of the current window frame. Store the
|
|
** results in the Window.regResult registers, ready to return the upper
|
|
** layer.
|
|
*/
|
|
static void windowFullScan(WindowCodeArg *p){
|
|
Window *pWin;
|
|
Parse *pParse = p->pParse;
|
|
Window *pMWin = p->pMWin;
|
|
Vdbe *v = p->pVdbe;
|
|
|
|
int regCRowid = 0; /* Current rowid value */
|
|
int regCPeer = 0; /* Current peer values */
|
|
int regRowid = 0; /* AggStep rowid value */
|
|
int regPeer = 0; /* AggStep peer values */
|
|
|
|
int nPeer;
|
|
int lblNext;
|
|
int lblBrk;
|
|
int addrNext;
|
|
int csr;
|
|
|
|
VdbeModuleComment((v, "windowFullScan begin"));
|
|
|
|
assert( pMWin!=0 );
|
|
csr = pMWin->csrApp;
|
|
nPeer = (pMWin->pOrderBy ? pMWin->pOrderBy->nExpr : 0);
|
|
|
|
lblNext = sqlite3VdbeMakeLabel(pParse);
|
|
lblBrk = sqlite3VdbeMakeLabel(pParse);
|
|
|
|
regCRowid = sqlite3GetTempReg(pParse);
|
|
regRowid = sqlite3GetTempReg(pParse);
|
|
if( nPeer ){
|
|
regCPeer = sqlite3GetTempRange(pParse, nPeer);
|
|
regPeer = sqlite3GetTempRange(pParse, nPeer);
|
|
}
|
|
|
|
sqlite3VdbeAddOp2(v, OP_Rowid, pMWin->iEphCsr, regCRowid);
|
|
windowReadPeerValues(p, pMWin->iEphCsr, regCPeer);
|
|
|
|
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regAccum);
|
|
}
|
|
|
|
sqlite3VdbeAddOp3(v, OP_SeekGE, csr, lblBrk, pMWin->regStartRowid);
|
|
VdbeCoverage(v);
|
|
addrNext = sqlite3VdbeCurrentAddr(v);
|
|
sqlite3VdbeAddOp2(v, OP_Rowid, csr, regRowid);
|
|
sqlite3VdbeAddOp3(v, OP_Gt, pMWin->regEndRowid, lblBrk, regRowid);
|
|
VdbeCoverageNeverNull(v);
|
|
|
|
if( pMWin->eExclude==TK_CURRENT ){
|
|
sqlite3VdbeAddOp3(v, OP_Eq, regCRowid, lblNext, regRowid);
|
|
VdbeCoverageNeverNull(v);
|
|
}else if( pMWin->eExclude!=TK_NO ){
|
|
int addr;
|
|
int addrEq = 0;
|
|
KeyInfo *pKeyInfo = 0;
|
|
|
|
if( pMWin->pOrderBy ){
|
|
pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pMWin->pOrderBy, 0, 0);
|
|
}
|
|
if( pMWin->eExclude==TK_TIES ){
|
|
addrEq = sqlite3VdbeAddOp3(v, OP_Eq, regCRowid, 0, regRowid);
|
|
VdbeCoverageNeverNull(v);
|
|
}
|
|
if( pKeyInfo ){
|
|
windowReadPeerValues(p, csr, regPeer);
|
|
sqlite3VdbeAddOp3(v, OP_Compare, regPeer, regCPeer, nPeer);
|
|
sqlite3VdbeAppendP4(v, (void*)pKeyInfo, P4_KEYINFO);
|
|
addr = sqlite3VdbeCurrentAddr(v)+1;
|
|
sqlite3VdbeAddOp3(v, OP_Jump, addr, lblNext, addr);
|
|
VdbeCoverageEqNe(v);
|
|
}else{
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, lblNext);
|
|
}
|
|
if( addrEq ) sqlite3VdbeJumpHere(v, addrEq);
|
|
}
|
|
|
|
windowAggStep(p, pMWin, csr, 0, p->regArg);
|
|
|
|
sqlite3VdbeResolveLabel(v, lblNext);
|
|
sqlite3VdbeAddOp2(v, OP_Next, csr, addrNext);
|
|
VdbeCoverage(v);
|
|
sqlite3VdbeJumpHere(v, addrNext-1);
|
|
sqlite3VdbeJumpHere(v, addrNext+1);
|
|
sqlite3ReleaseTempReg(pParse, regRowid);
|
|
sqlite3ReleaseTempReg(pParse, regCRowid);
|
|
if( nPeer ){
|
|
sqlite3ReleaseTempRange(pParse, regPeer, nPeer);
|
|
sqlite3ReleaseTempRange(pParse, regCPeer, nPeer);
|
|
}
|
|
|
|
windowAggFinal(p, 1);
|
|
VdbeModuleComment((v, "windowFullScan end"));
|
|
}
|
|
|
|
/*
|
|
** Invoke the sub-routine at regGosub (generated by code in select.c) to
|
|
** return the current row of Window.iEphCsr. If all window functions are
|
|
** aggregate window functions that use the standard API, a single
|
|
** OP_Gosub instruction is all that this routine generates. Extra VM code
|
|
** for per-row processing is only generated for the following built-in window
|
|
** functions:
|
|
**
|
|
** nth_value()
|
|
** first_value()
|
|
** lag()
|
|
** lead()
|
|
*/
|
|
static void windowReturnOneRow(WindowCodeArg *p){
|
|
Window *pMWin = p->pMWin;
|
|
Vdbe *v = p->pVdbe;
|
|
|
|
if( pMWin->regStartRowid ){
|
|
windowFullScan(p);
|
|
}else{
|
|
Parse *pParse = p->pParse;
|
|
Window *pWin;
|
|
|
|
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
|
|
FuncDef *pFunc = pWin->pWFunc;
|
|
assert( ExprUseXList(pWin->pOwner) );
|
|
if( pFunc->zName==nth_valueName
|
|
|| pFunc->zName==first_valueName
|
|
){
|
|
int csr = pWin->csrApp;
|
|
int lbl = sqlite3VdbeMakeLabel(pParse);
|
|
int tmpReg = sqlite3GetTempReg(pParse);
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regResult);
|
|
|
|
if( pFunc->zName==nth_valueName ){
|
|
sqlite3VdbeAddOp3(v, OP_Column,pMWin->iEphCsr,pWin->iArgCol+1,tmpReg);
|
|
windowCheckValue(pParse, tmpReg, 2);
|
|
}else{
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, tmpReg);
|
|
}
|
|
sqlite3VdbeAddOp3(v, OP_Add, tmpReg, pWin->regApp, tmpReg);
|
|
sqlite3VdbeAddOp3(v, OP_Gt, pWin->regApp+1, lbl, tmpReg);
|
|
VdbeCoverageNeverNull(v);
|
|
sqlite3VdbeAddOp3(v, OP_SeekRowid, csr, 0, tmpReg);
|
|
VdbeCoverageNeverTaken(v);
|
|
sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol, pWin->regResult);
|
|
sqlite3VdbeResolveLabel(v, lbl);
|
|
sqlite3ReleaseTempReg(pParse, tmpReg);
|
|
}
|
|
else if( pFunc->zName==leadName || pFunc->zName==lagName ){
|
|
int nArg = pWin->pOwner->x.pList->nExpr;
|
|
int csr = pWin->csrApp;
|
|
int lbl = sqlite3VdbeMakeLabel(pParse);
|
|
int tmpReg = sqlite3GetTempReg(pParse);
|
|
int iEph = pMWin->iEphCsr;
|
|
|
|
if( nArg<3 ){
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regResult);
|
|
}else{
|
|
sqlite3VdbeAddOp3(v, OP_Column, iEph,pWin->iArgCol+2,pWin->regResult);
|
|
}
|
|
sqlite3VdbeAddOp2(v, OP_Rowid, iEph, tmpReg);
|
|
if( nArg<2 ){
|
|
int val = (pFunc->zName==leadName ? 1 : -1);
|
|
sqlite3VdbeAddOp2(v, OP_AddImm, tmpReg, val);
|
|
}else{
|
|
int op = (pFunc->zName==leadName ? OP_Add : OP_Subtract);
|
|
int tmpReg2 = sqlite3GetTempReg(pParse);
|
|
sqlite3VdbeAddOp3(v, OP_Column, iEph, pWin->iArgCol+1, tmpReg2);
|
|
sqlite3VdbeAddOp3(v, op, tmpReg2, tmpReg, tmpReg);
|
|
sqlite3ReleaseTempReg(pParse, tmpReg2);
|
|
}
|
|
|
|
sqlite3VdbeAddOp3(v, OP_SeekRowid, csr, lbl, tmpReg);
|
|
VdbeCoverage(v);
|
|
sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol, pWin->regResult);
|
|
sqlite3VdbeResolveLabel(v, lbl);
|
|
sqlite3ReleaseTempReg(pParse, tmpReg);
|
|
}
|
|
}
|
|
}
|
|
sqlite3VdbeAddOp2(v, OP_Gosub, p->regGosub, p->addrGosub);
|
|
}
|
|
|
|
/*
|
|
** Generate code to set the accumulator register for each window function
|
|
** in the linked list passed as the second argument to NULL. And perform
|
|
** any equivalent initialization required by any built-in window functions
|
|
** in the list.
|
|
*/
|
|
static int windowInitAccum(Parse *pParse, Window *pMWin){
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
int regArg;
|
|
int nArg = 0;
|
|
Window *pWin;
|
|
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
|
|
FuncDef *pFunc = pWin->pWFunc;
|
|
assert( pWin->regAccum );
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regAccum);
|
|
nArg = MAX(nArg, windowArgCount(pWin));
|
|
if( pMWin->regStartRowid==0 ){
|
|
if( pFunc->zName==nth_valueName || pFunc->zName==first_valueName ){
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, pWin->regApp);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, pWin->regApp+1);
|
|
}
|
|
|
|
if( (pFunc->funcFlags & SQLITE_FUNC_MINMAX) && pWin->csrApp ){
|
|
assert( pWin->eStart!=TK_UNBOUNDED );
|
|
sqlite3VdbeAddOp1(v, OP_ResetSorter, pWin->csrApp);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, pWin->regApp+1);
|
|
}
|
|
}
|
|
}
|
|
regArg = pParse->nMem+1;
|
|
pParse->nMem += nArg;
|
|
return regArg;
|
|
}
|
|
|
|
/*
|
|
** Return true if the current frame should be cached in the ephemeral table,
|
|
** even if there are no xInverse() calls required.
|
|
*/
|
|
static int windowCacheFrame(Window *pMWin){
|
|
Window *pWin;
|
|
if( pMWin->regStartRowid ) return 1;
|
|
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
|
|
FuncDef *pFunc = pWin->pWFunc;
|
|
if( (pFunc->zName==nth_valueName)
|
|
|| (pFunc->zName==first_valueName)
|
|
|| (pFunc->zName==leadName)
|
|
|| (pFunc->zName==lagName)
|
|
){
|
|
return 1;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
** regOld and regNew are each the first register in an array of size
|
|
** pOrderBy->nExpr. This function generates code to compare the two
|
|
** arrays of registers using the collation sequences and other comparison
|
|
** parameters specified by pOrderBy.
|
|
**
|
|
** If the two arrays are not equal, the contents of regNew is copied to
|
|
** regOld and control falls through. Otherwise, if the contents of the arrays
|
|
** are equal, an OP_Goto is executed. The address of the OP_Goto is returned.
|
|
*/
|
|
static void windowIfNewPeer(
|
|
Parse *pParse,
|
|
ExprList *pOrderBy,
|
|
int regNew, /* First in array of new values */
|
|
int regOld, /* First in array of old values */
|
|
int addr /* Jump here */
|
|
){
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
if( pOrderBy ){
|
|
int nVal = pOrderBy->nExpr;
|
|
KeyInfo *pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pOrderBy, 0, 0);
|
|
sqlite3VdbeAddOp3(v, OP_Compare, regOld, regNew, nVal);
|
|
sqlite3VdbeAppendP4(v, (void*)pKeyInfo, P4_KEYINFO);
|
|
sqlite3VdbeAddOp3(v, OP_Jump,
|
|
sqlite3VdbeCurrentAddr(v)+1, addr, sqlite3VdbeCurrentAddr(v)+1
|
|
);
|
|
VdbeCoverageEqNe(v);
|
|
sqlite3VdbeAddOp3(v, OP_Copy, regNew, regOld, nVal-1);
|
|
}else{
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** This function is called as part of generating VM programs for RANGE
|
|
** offset PRECEDING/FOLLOWING frame boundaries. Assuming "ASC" order for
|
|
** the ORDER BY term in the window, and that argument op is OP_Ge, it generates
|
|
** code equivalent to:
|
|
**
|
|
** if( csr1.peerVal + regVal >= csr2.peerVal ) goto lbl;
|
|
**
|
|
** The value of parameter op may also be OP_Gt or OP_Le. In these cases the
|
|
** operator in the above pseudo-code is replaced with ">" or "<=", respectively.
|
|
**
|
|
** If the sort-order for the ORDER BY term in the window is DESC, then the
|
|
** comparison is reversed. Instead of adding regVal to csr1.peerVal, it is
|
|
** subtracted. And the comparison operator is inverted to - ">=" becomes "<=",
|
|
** ">" becomes "<", and so on. So, with DESC sort order, if the argument op
|
|
** is OP_Ge, the generated code is equivalent to:
|
|
**
|
|
** if( csr1.peerVal - regVal <= csr2.peerVal ) goto lbl;
|
|
**
|
|
** A special type of arithmetic is used such that if csr1.peerVal is not
|
|
** a numeric type (real or integer), then the result of the addition
|
|
** or subtraction is a a copy of csr1.peerVal.
|
|
*/
|
|
static void windowCodeRangeTest(
|
|
WindowCodeArg *p,
|
|
int op, /* OP_Ge, OP_Gt, or OP_Le */
|
|
int csr1, /* Cursor number for cursor 1 */
|
|
int regVal, /* Register containing non-negative number */
|
|
int csr2, /* Cursor number for cursor 2 */
|
|
int lbl /* Jump destination if condition is true */
|
|
){
|
|
Parse *pParse = p->pParse;
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
ExprList *pOrderBy = p->pMWin->pOrderBy; /* ORDER BY clause for window */
|
|
int reg1 = sqlite3GetTempReg(pParse); /* Reg. for csr1.peerVal+regVal */
|
|
int reg2 = sqlite3GetTempReg(pParse); /* Reg. for csr2.peerVal */
|
|
int regString = ++pParse->nMem; /* Reg. for constant value '' */
|
|
int arith = OP_Add; /* OP_Add or OP_Subtract */
|
|
int addrGe; /* Jump destination */
|
|
int addrDone = sqlite3VdbeMakeLabel(pParse); /* Address past OP_Ge */
|
|
CollSeq *pColl;
|
|
|
|
/* Read the peer-value from each cursor into a register */
|
|
windowReadPeerValues(p, csr1, reg1);
|
|
windowReadPeerValues(p, csr2, reg2);
|
|
|
|
assert( op==OP_Ge || op==OP_Gt || op==OP_Le );
|
|
assert( pOrderBy && pOrderBy->nExpr==1 );
|
|
if( pOrderBy->a[0].fg.sortFlags & KEYINFO_ORDER_DESC ){
|
|
switch( op ){
|
|
case OP_Ge: op = OP_Le; break;
|
|
case OP_Gt: op = OP_Lt; break;
|
|
default: assert( op==OP_Le ); op = OP_Ge; break;
|
|
}
|
|
arith = OP_Subtract;
|
|
}
|
|
|
|
VdbeModuleComment((v, "CodeRangeTest: if( R%d %s R%d %s R%d ) goto lbl",
|
|
reg1, (arith==OP_Add ? "+" : "-"), regVal,
|
|
((op==OP_Ge) ? ">=" : (op==OP_Le) ? "<=" : (op==OP_Gt) ? ">" : "<"), reg2
|
|
));
|
|
|
|
/* If the BIGNULL flag is set for the ORDER BY, then it is required to
|
|
** consider NULL values to be larger than all other values, instead of
|
|
** the usual smaller. The VDBE opcodes OP_Ge and so on do not handle this
|
|
** (and adding that capability causes a performance regression), so
|
|
** instead if the BIGNULL flag is set then cases where either reg1 or
|
|
** reg2 are NULL are handled separately in the following block. The code
|
|
** generated is equivalent to:
|
|
**
|
|
** if( reg1 IS NULL ){
|
|
** if( op==OP_Ge ) goto lbl;
|
|
** if( op==OP_Gt && reg2 IS NOT NULL ) goto lbl;
|
|
** if( op==OP_Le && reg2 IS NULL ) goto lbl;
|
|
** }else if( reg2 IS NULL ){
|
|
** if( op==OP_Le ) goto lbl;
|
|
** }
|
|
**
|
|
** Additionally, if either reg1 or reg2 are NULL but the jump to lbl is
|
|
** not taken, control jumps over the comparison operator coded below this
|
|
** block. */
|
|
if( pOrderBy->a[0].fg.sortFlags & KEYINFO_ORDER_BIGNULL ){
|
|
/* This block runs if reg1 contains a NULL. */
|
|
int addr = sqlite3VdbeAddOp1(v, OP_NotNull, reg1); VdbeCoverage(v);
|
|
switch( op ){
|
|
case OP_Ge:
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, lbl);
|
|
break;
|
|
case OP_Gt:
|
|
sqlite3VdbeAddOp2(v, OP_NotNull, reg2, lbl);
|
|
VdbeCoverage(v);
|
|
break;
|
|
case OP_Le:
|
|
sqlite3VdbeAddOp2(v, OP_IsNull, reg2, lbl);
|
|
VdbeCoverage(v);
|
|
break;
|
|
default: assert( op==OP_Lt ); /* no-op */ break;
|
|
}
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrDone);
|
|
|
|
/* This block runs if reg1 is not NULL, but reg2 is. */
|
|
sqlite3VdbeJumpHere(v, addr);
|
|
sqlite3VdbeAddOp2(v, OP_IsNull, reg2,
|
|
(op==OP_Gt || op==OP_Ge) ? addrDone : lbl);
|
|
VdbeCoverage(v);
|
|
}
|
|
|
|
/* Register reg1 currently contains csr1.peerVal (the peer-value from csr1).
|
|
** This block adds (or subtracts for DESC) the numeric value in regVal
|
|
** from it. Or, if reg1 is not numeric (it is a NULL, a text value or a blob),
|
|
** then leave reg1 as it is. In pseudo-code, this is implemented as:
|
|
**
|
|
** if( reg1>='' ) goto addrGe;
|
|
** reg1 = reg1 +/- regVal
|
|
** addrGe:
|
|
**
|
|
** Since all strings and blobs are greater-than-or-equal-to an empty string,
|
|
** the add/subtract is skipped for these, as required. If reg1 is a NULL,
|
|
** then the arithmetic is performed, but since adding or subtracting from
|
|
** NULL is always NULL anyway, this case is handled as required too. */
|
|
sqlite3VdbeAddOp4(v, OP_String8, 0, regString, 0, "", P4_STATIC);
|
|
addrGe = sqlite3VdbeAddOp3(v, OP_Ge, regString, 0, reg1);
|
|
VdbeCoverage(v);
|
|
if( (op==OP_Ge && arith==OP_Add) || (op==OP_Le && arith==OP_Subtract) ){
|
|
sqlite3VdbeAddOp3(v, op, reg2, lbl, reg1); VdbeCoverage(v);
|
|
}
|
|
sqlite3VdbeAddOp3(v, arith, regVal, reg1, reg1);
|
|
sqlite3VdbeJumpHere(v, addrGe);
|
|
|
|
/* Compare registers reg2 and reg1, taking the jump if required. Note that
|
|
** control skips over this test if the BIGNULL flag is set and either
|
|
** reg1 or reg2 contain a NULL value. */
|
|
sqlite3VdbeAddOp3(v, op, reg2, lbl, reg1); VdbeCoverage(v);
|
|
pColl = sqlite3ExprNNCollSeq(pParse, pOrderBy->a[0].pExpr);
|
|
sqlite3VdbeAppendP4(v, (void*)pColl, P4_COLLSEQ);
|
|
sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
|
|
sqlite3VdbeResolveLabel(v, addrDone);
|
|
|
|
assert( op==OP_Ge || op==OP_Gt || op==OP_Lt || op==OP_Le );
|
|
testcase(op==OP_Ge); VdbeCoverageIf(v, op==OP_Ge);
|
|
testcase(op==OP_Lt); VdbeCoverageIf(v, op==OP_Lt);
|
|
testcase(op==OP_Le); VdbeCoverageIf(v, op==OP_Le);
|
|
testcase(op==OP_Gt); VdbeCoverageIf(v, op==OP_Gt);
|
|
sqlite3ReleaseTempReg(pParse, reg1);
|
|
sqlite3ReleaseTempReg(pParse, reg2);
|
|
|
|
VdbeModuleComment((v, "CodeRangeTest: end"));
|
|
}
|
|
|
|
/*
|
|
** Helper function for sqlite3WindowCodeStep(). Each call to this function
|
|
** generates VM code for a single RETURN_ROW, AGGSTEP or AGGINVERSE
|
|
** operation. Refer to the header comment for sqlite3WindowCodeStep() for
|
|
** details.
|
|
*/
|
|
static int windowCodeOp(
|
|
WindowCodeArg *p, /* Context object */
|
|
int op, /* WINDOW_RETURN_ROW, AGGSTEP or AGGINVERSE */
|
|
int regCountdown, /* Register for OP_IfPos countdown */
|
|
int jumpOnEof /* Jump here if stepped cursor reaches EOF */
|
|
){
|
|
int csr, reg;
|
|
Parse *pParse = p->pParse;
|
|
Window *pMWin = p->pMWin;
|
|
int ret = 0;
|
|
Vdbe *v = p->pVdbe;
|
|
int addrContinue = 0;
|
|
int bPeer = (pMWin->eFrmType!=TK_ROWS);
|
|
|
|
int lblDone = sqlite3VdbeMakeLabel(pParse);
|
|
int addrNextRange = 0;
|
|
|
|
/* Special case - WINDOW_AGGINVERSE is always a no-op if the frame
|
|
** starts with UNBOUNDED PRECEDING. */
|
|
if( op==WINDOW_AGGINVERSE && pMWin->eStart==TK_UNBOUNDED ){
|
|
assert( regCountdown==0 && jumpOnEof==0 );
|
|
return 0;
|
|
}
|
|
|
|
if( regCountdown>0 ){
|
|
if( pMWin->eFrmType==TK_RANGE ){
|
|
addrNextRange = sqlite3VdbeCurrentAddr(v);
|
|
assert( op==WINDOW_AGGINVERSE || op==WINDOW_AGGSTEP );
|
|
if( op==WINDOW_AGGINVERSE ){
|
|
if( pMWin->eStart==TK_FOLLOWING ){
|
|
windowCodeRangeTest(
|
|
p, OP_Le, p->current.csr, regCountdown, p->start.csr, lblDone
|
|
);
|
|
}else{
|
|
windowCodeRangeTest(
|
|
p, OP_Ge, p->start.csr, regCountdown, p->current.csr, lblDone
|
|
);
|
|
}
|
|
}else{
|
|
windowCodeRangeTest(
|
|
p, OP_Gt, p->end.csr, regCountdown, p->current.csr, lblDone
|
|
);
|
|
}
|
|
}else{
|
|
sqlite3VdbeAddOp3(v, OP_IfPos, regCountdown, lblDone, 1);
|
|
VdbeCoverage(v);
|
|
}
|
|
}
|
|
|
|
if( op==WINDOW_RETURN_ROW && pMWin->regStartRowid==0 ){
|
|
windowAggFinal(p, 0);
|
|
}
|
|
addrContinue = sqlite3VdbeCurrentAddr(v);
|
|
|
|
/* If this is a (RANGE BETWEEN a FOLLOWING AND b FOLLOWING) or
|
|
** (RANGE BETWEEN b PRECEDING AND a PRECEDING) frame, ensure the
|
|
** start cursor does not advance past the end cursor within the
|
|
** temporary table. It otherwise might, if (a>b). Also ensure that,
|
|
** if the input cursor is still finding new rows, that the end
|
|
** cursor does not go past it to EOF. */
|
|
if( pMWin->eStart==pMWin->eEnd && regCountdown
|
|
&& pMWin->eFrmType==TK_RANGE
|
|
){
|
|
int regRowid1 = sqlite3GetTempReg(pParse);
|
|
int regRowid2 = sqlite3GetTempReg(pParse);
|
|
if( op==WINDOW_AGGINVERSE ){
|
|
sqlite3VdbeAddOp2(v, OP_Rowid, p->start.csr, regRowid1);
|
|
sqlite3VdbeAddOp2(v, OP_Rowid, p->end.csr, regRowid2);
|
|
sqlite3VdbeAddOp3(v, OP_Ge, regRowid2, lblDone, regRowid1);
|
|
VdbeCoverage(v);
|
|
}else if( p->regRowid ){
|
|
sqlite3VdbeAddOp2(v, OP_Rowid, p->end.csr, regRowid1);
|
|
sqlite3VdbeAddOp3(v, OP_Ge, p->regRowid, lblDone, regRowid1);
|
|
VdbeCoverageNeverNull(v);
|
|
}
|
|
sqlite3ReleaseTempReg(pParse, regRowid1);
|
|
sqlite3ReleaseTempReg(pParse, regRowid2);
|
|
assert( pMWin->eStart==TK_PRECEDING || pMWin->eStart==TK_FOLLOWING );
|
|
}
|
|
|
|
switch( op ){
|
|
case WINDOW_RETURN_ROW:
|
|
csr = p->current.csr;
|
|
reg = p->current.reg;
|
|
windowReturnOneRow(p);
|
|
break;
|
|
|
|
case WINDOW_AGGINVERSE:
|
|
csr = p->start.csr;
|
|
reg = p->start.reg;
|
|
if( pMWin->regStartRowid ){
|
|
assert( pMWin->regEndRowid );
|
|
sqlite3VdbeAddOp2(v, OP_AddImm, pMWin->regStartRowid, 1);
|
|
}else{
|
|
windowAggStep(p, pMWin, csr, 1, p->regArg);
|
|
}
|
|
break;
|
|
|
|
default:
|
|
assert( op==WINDOW_AGGSTEP );
|
|
csr = p->end.csr;
|
|
reg = p->end.reg;
|
|
if( pMWin->regStartRowid ){
|
|
assert( pMWin->regEndRowid );
|
|
sqlite3VdbeAddOp2(v, OP_AddImm, pMWin->regEndRowid, 1);
|
|
}else{
|
|
windowAggStep(p, pMWin, csr, 0, p->regArg);
|
|
}
|
|
break;
|
|
}
|
|
|
|
if( op==p->eDelete ){
|
|
sqlite3VdbeAddOp1(v, OP_Delete, csr);
|
|
sqlite3VdbeChangeP5(v, OPFLAG_SAVEPOSITION);
|
|
}
|
|
|
|
if( jumpOnEof ){
|
|
sqlite3VdbeAddOp2(v, OP_Next, csr, sqlite3VdbeCurrentAddr(v)+2);
|
|
VdbeCoverage(v);
|
|
ret = sqlite3VdbeAddOp0(v, OP_Goto);
|
|
}else{
|
|
sqlite3VdbeAddOp2(v, OP_Next, csr, sqlite3VdbeCurrentAddr(v)+1+bPeer);
|
|
VdbeCoverage(v);
|
|
if( bPeer ){
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, lblDone);
|
|
}
|
|
}
|
|
|
|
if( bPeer ){
|
|
int nReg = (pMWin->pOrderBy ? pMWin->pOrderBy->nExpr : 0);
|
|
int regTmp = (nReg ? sqlite3GetTempRange(pParse, nReg) : 0);
|
|
windowReadPeerValues(p, csr, regTmp);
|
|
windowIfNewPeer(pParse, pMWin->pOrderBy, regTmp, reg, addrContinue);
|
|
sqlite3ReleaseTempRange(pParse, regTmp, nReg);
|
|
}
|
|
|
|
if( addrNextRange ){
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrNextRange);
|
|
}
|
|
sqlite3VdbeResolveLabel(v, lblDone);
|
|
return ret;
|
|
}
|
|
|
|
|
|
/*
|
|
** Allocate and return a duplicate of the Window object indicated by the
|
|
** third argument. Set the Window.pOwner field of the new object to
|
|
** pOwner.
|
|
*/
|
|
Window *sqlite3WindowDup(sqlite3 *db, Expr *pOwner, Window *p){
|
|
Window *pNew = 0;
|
|
if( ALWAYS(p) ){
|
|
pNew = sqlite3DbMallocZero(db, sizeof(Window));
|
|
if( pNew ){
|
|
pNew->zName = sqlite3DbStrDup(db, p->zName);
|
|
pNew->zBase = sqlite3DbStrDup(db, p->zBase);
|
|
pNew->pFilter = sqlite3ExprDup(db, p->pFilter, 0);
|
|
pNew->pWFunc = p->pWFunc;
|
|
pNew->pPartition = sqlite3ExprListDup(db, p->pPartition, 0);
|
|
pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy, 0);
|
|
pNew->eFrmType = p->eFrmType;
|
|
pNew->eEnd = p->eEnd;
|
|
pNew->eStart = p->eStart;
|
|
pNew->eExclude = p->eExclude;
|
|
pNew->regResult = p->regResult;
|
|
pNew->regAccum = p->regAccum;
|
|
pNew->iArgCol = p->iArgCol;
|
|
pNew->iEphCsr = p->iEphCsr;
|
|
pNew->bExprArgs = p->bExprArgs;
|
|
pNew->pStart = sqlite3ExprDup(db, p->pStart, 0);
|
|
pNew->pEnd = sqlite3ExprDup(db, p->pEnd, 0);
|
|
pNew->pOwner = pOwner;
|
|
pNew->bImplicitFrame = p->bImplicitFrame;
|
|
}
|
|
}
|
|
return pNew;
|
|
}
|
|
|
|
/*
|
|
** Return a copy of the linked list of Window objects passed as the
|
|
** second argument.
|
|
*/
|
|
Window *sqlite3WindowListDup(sqlite3 *db, Window *p){
|
|
Window *pWin;
|
|
Window *pRet = 0;
|
|
Window **pp = &pRet;
|
|
|
|
for(pWin=p; pWin; pWin=pWin->pNextWin){
|
|
*pp = sqlite3WindowDup(db, 0, pWin);
|
|
if( *pp==0 ) break;
|
|
pp = &((*pp)->pNextWin);
|
|
}
|
|
|
|
return pRet;
|
|
}
|
|
|
|
/*
|
|
** Return true if it can be determined at compile time that expression
|
|
** pExpr evaluates to a value that, when cast to an integer, is greater
|
|
** than zero. False otherwise.
|
|
**
|
|
** If an OOM error occurs, this function sets the Parse.db.mallocFailed
|
|
** flag and returns zero.
|
|
*/
|
|
static int windowExprGtZero(Parse *pParse, Expr *pExpr){
|
|
int ret = 0;
|
|
sqlite3 *db = pParse->db;
|
|
sqlite3_value *pVal = 0;
|
|
sqlite3ValueFromExpr(db, pExpr, db->enc, SQLITE_AFF_NUMERIC, &pVal);
|
|
if( pVal && sqlite3_value_int(pVal)>0 ){
|
|
ret = 1;
|
|
}
|
|
sqlite3ValueFree(pVal);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
** sqlite3WhereBegin() has already been called for the SELECT statement
|
|
** passed as the second argument when this function is invoked. It generates
|
|
** code to populate the Window.regResult register for each window function
|
|
** and invoke the sub-routine at instruction addrGosub once for each row.
|
|
** sqlite3WhereEnd() is always called before returning.
|
|
**
|
|
** This function handles several different types of window frames, which
|
|
** require slightly different processing. The following pseudo code is
|
|
** used to implement window frames of the form:
|
|
**
|
|
** ROWS BETWEEN <expr1> PRECEDING AND <expr2> FOLLOWING
|
|
**
|
|
** Other window frame types use variants of the following:
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
**
|
|
** if( first row of partition ){
|
|
** // Rewind three cursors, all open on the eph table.
|
|
** Rewind(csrEnd);
|
|
** Rewind(csrStart);
|
|
** Rewind(csrCurrent);
|
|
**
|
|
** regEnd = <expr2> // FOLLOWING expression
|
|
** regStart = <expr1> // PRECEDING expression
|
|
** }else{
|
|
** // First time this branch is taken, the eph table contains two
|
|
** // rows. The first row in the partition, which all three cursors
|
|
** // currently point to, and the following row.
|
|
** AGGSTEP
|
|
** if( (regEnd--)<=0 ){
|
|
** RETURN_ROW
|
|
** if( (regStart--)<=0 ){
|
|
** AGGINVERSE
|
|
** }
|
|
** }
|
|
** }
|
|
** }
|
|
** flush:
|
|
** AGGSTEP
|
|
** while( 1 ){
|
|
** RETURN ROW
|
|
** if( csrCurrent is EOF ) break;
|
|
** if( (regStart--)<=0 ){
|
|
** AggInverse(csrStart)
|
|
** Next(csrStart)
|
|
** }
|
|
** }
|
|
**
|
|
** The pseudo-code above uses the following shorthand:
|
|
**
|
|
** AGGSTEP: invoke the aggregate xStep() function for each window function
|
|
** with arguments read from the current row of cursor csrEnd, then
|
|
** step cursor csrEnd forward one row (i.e. sqlite3BtreeNext()).
|
|
**
|
|
** RETURN_ROW: return a row to the caller based on the contents of the
|
|
** current row of csrCurrent and the current state of all
|
|
** aggregates. Then step cursor csrCurrent forward one row.
|
|
**
|
|
** AGGINVERSE: invoke the aggregate xInverse() function for each window
|
|
** functions with arguments read from the current row of cursor
|
|
** csrStart. Then step csrStart forward one row.
|
|
**
|
|
** There are two other ROWS window frames that are handled significantly
|
|
** differently from the above - "BETWEEN <expr> PRECEDING AND <expr> PRECEDING"
|
|
** and "BETWEEN <expr> FOLLOWING AND <expr> FOLLOWING". These are special
|
|
** cases because they change the order in which the three cursors (csrStart,
|
|
** csrCurrent and csrEnd) iterate through the ephemeral table. Cases that
|
|
** use UNBOUNDED or CURRENT ROW are much simpler variations on one of these
|
|
** three.
|
|
**
|
|
** ROWS BETWEEN <expr1> PRECEDING AND <expr2> PRECEDING
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
** if( first row of partition ){
|
|
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
|
|
** regEnd = <expr2>
|
|
** regStart = <expr1>
|
|
** }else{
|
|
** if( (regEnd--)<=0 ){
|
|
** AGGSTEP
|
|
** }
|
|
** RETURN_ROW
|
|
** if( (regStart--)<=0 ){
|
|
** AGGINVERSE
|
|
** }
|
|
** }
|
|
** }
|
|
** flush:
|
|
** if( (regEnd--)<=0 ){
|
|
** AGGSTEP
|
|
** }
|
|
** RETURN_ROW
|
|
**
|
|
**
|
|
** ROWS BETWEEN <expr1> FOLLOWING AND <expr2> FOLLOWING
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
** if( first row of partition ){
|
|
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
|
|
** regEnd = <expr2>
|
|
** regStart = regEnd - <expr1>
|
|
** }else{
|
|
** AGGSTEP
|
|
** if( (regEnd--)<=0 ){
|
|
** RETURN_ROW
|
|
** }
|
|
** if( (regStart--)<=0 ){
|
|
** AGGINVERSE
|
|
** }
|
|
** }
|
|
** }
|
|
** flush:
|
|
** AGGSTEP
|
|
** while( 1 ){
|
|
** if( (regEnd--)<=0 ){
|
|
** RETURN_ROW
|
|
** if( eof ) break;
|
|
** }
|
|
** if( (regStart--)<=0 ){
|
|
** AGGINVERSE
|
|
** if( eof ) break
|
|
** }
|
|
** }
|
|
** while( !eof csrCurrent ){
|
|
** RETURN_ROW
|
|
** }
|
|
**
|
|
** For the most part, the patterns above are adapted to support UNBOUNDED by
|
|
** assuming that it is equivalent to "infinity PRECEDING/FOLLOWING" and
|
|
** CURRENT ROW by assuming that it is equivilent to "0 PRECEDING/FOLLOWING".
|
|
** This is optimized of course - branches that will never be taken and
|
|
** conditions that are always true are omitted from the VM code. The only
|
|
** exceptional case is:
|
|
**
|
|
** ROWS BETWEEN <expr1> FOLLOWING AND UNBOUNDED FOLLOWING
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
** if( first row of partition ){
|
|
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
|
|
** regStart = <expr1>
|
|
** }else{
|
|
** AGGSTEP
|
|
** }
|
|
** }
|
|
** flush:
|
|
** AGGSTEP
|
|
** while( 1 ){
|
|
** if( (regStart--)<=0 ){
|
|
** AGGINVERSE
|
|
** if( eof ) break
|
|
** }
|
|
** RETURN_ROW
|
|
** }
|
|
** while( !eof csrCurrent ){
|
|
** RETURN_ROW
|
|
** }
|
|
**
|
|
** Also requiring special handling are the cases:
|
|
**
|
|
** ROWS BETWEEN <expr1> PRECEDING AND <expr2> PRECEDING
|
|
** ROWS BETWEEN <expr1> FOLLOWING AND <expr2> FOLLOWING
|
|
**
|
|
** when (expr1 < expr2). This is detected at runtime, not by this function.
|
|
** To handle this case, the pseudo-code programs depicted above are modified
|
|
** slightly to be:
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
** if( first row of partition ){
|
|
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
|
|
** regEnd = <expr2>
|
|
** regStart = <expr1>
|
|
** if( regEnd < regStart ){
|
|
** RETURN_ROW
|
|
** delete eph table contents
|
|
** continue
|
|
** }
|
|
** ...
|
|
**
|
|
** The new "continue" statement in the above jumps to the next iteration
|
|
** of the outer loop - the one started by sqlite3WhereBegin().
|
|
**
|
|
** The various GROUPS cases are implemented using the same patterns as
|
|
** ROWS. The VM code is modified slightly so that:
|
|
**
|
|
** 1. The else branch in the main loop is only taken if the row just
|
|
** added to the ephemeral table is the start of a new group. In
|
|
** other words, it becomes:
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
** if( first row of partition ){
|
|
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
|
|
** regEnd = <expr2>
|
|
** regStart = <expr1>
|
|
** }else if( new group ){
|
|
** ...
|
|
** }
|
|
** }
|
|
**
|
|
** 2. Instead of processing a single row, each RETURN_ROW, AGGSTEP or
|
|
** AGGINVERSE step processes the current row of the relevant cursor and
|
|
** all subsequent rows belonging to the same group.
|
|
**
|
|
** RANGE window frames are a little different again. As for GROUPS, the
|
|
** main loop runs once per group only. And RETURN_ROW, AGGSTEP and AGGINVERSE
|
|
** deal in groups instead of rows. As for ROWS and GROUPS, there are three
|
|
** basic cases:
|
|
**
|
|
** RANGE BETWEEN <expr1> PRECEDING AND <expr2> FOLLOWING
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
** if( first row of partition ){
|
|
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
|
|
** regEnd = <expr2>
|
|
** regStart = <expr1>
|
|
** }else{
|
|
** AGGSTEP
|
|
** while( (csrCurrent.key + regEnd) < csrEnd.key ){
|
|
** RETURN_ROW
|
|
** while( csrStart.key + regStart) < csrCurrent.key ){
|
|
** AGGINVERSE
|
|
** }
|
|
** }
|
|
** }
|
|
** }
|
|
** flush:
|
|
** AGGSTEP
|
|
** while( 1 ){
|
|
** RETURN ROW
|
|
** if( csrCurrent is EOF ) break;
|
|
** while( csrStart.key + regStart) < csrCurrent.key ){
|
|
** AGGINVERSE
|
|
** }
|
|
** }
|
|
** }
|
|
**
|
|
** In the above notation, "csr.key" means the current value of the ORDER BY
|
|
** expression (there is only ever 1 for a RANGE that uses an <expr> FOLLOWING
|
|
** or <expr PRECEDING) read from cursor csr.
|
|
**
|
|
** RANGE BETWEEN <expr1> PRECEDING AND <expr2> PRECEDING
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
** if( first row of partition ){
|
|
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
|
|
** regEnd = <expr2>
|
|
** regStart = <expr1>
|
|
** }else{
|
|
** while( (csrEnd.key + regEnd) <= csrCurrent.key ){
|
|
** AGGSTEP
|
|
** }
|
|
** while( (csrStart.key + regStart) < csrCurrent.key ){
|
|
** AGGINVERSE
|
|
** }
|
|
** RETURN_ROW
|
|
** }
|
|
** }
|
|
** flush:
|
|
** while( (csrEnd.key + regEnd) <= csrCurrent.key ){
|
|
** AGGSTEP
|
|
** }
|
|
** while( (csrStart.key + regStart) < csrCurrent.key ){
|
|
** AGGINVERSE
|
|
** }
|
|
** RETURN_ROW
|
|
**
|
|
** RANGE BETWEEN <expr1> FOLLOWING AND <expr2> FOLLOWING
|
|
**
|
|
** ... loop started by sqlite3WhereBegin() ...
|
|
** if( new partition ){
|
|
** Gosub flush
|
|
** }
|
|
** Insert new row into eph table.
|
|
** if( first row of partition ){
|
|
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
|
|
** regEnd = <expr2>
|
|
** regStart = <expr1>
|
|
** }else{
|
|
** AGGSTEP
|
|
** while( (csrCurrent.key + regEnd) < csrEnd.key ){
|
|
** while( (csrCurrent.key + regStart) > csrStart.key ){
|
|
** AGGINVERSE
|
|
** }
|
|
** RETURN_ROW
|
|
** }
|
|
** }
|
|
** }
|
|
** flush:
|
|
** AGGSTEP
|
|
** while( 1 ){
|
|
** while( (csrCurrent.key + regStart) > csrStart.key ){
|
|
** AGGINVERSE
|
|
** if( eof ) break "while( 1 )" loop.
|
|
** }
|
|
** RETURN_ROW
|
|
** }
|
|
** while( !eof csrCurrent ){
|
|
** RETURN_ROW
|
|
** }
|
|
**
|
|
** The text above leaves out many details. Refer to the code and comments
|
|
** below for a more complete picture.
|
|
*/
|
|
void sqlite3WindowCodeStep(
|
|
Parse *pParse, /* Parse context */
|
|
Select *p, /* Rewritten SELECT statement */
|
|
WhereInfo *pWInfo, /* Context returned by sqlite3WhereBegin() */
|
|
int regGosub, /* Register for OP_Gosub */
|
|
int addrGosub /* OP_Gosub here to return each row */
|
|
){
|
|
Window *pMWin = p->pWin;
|
|
ExprList *pOrderBy = pMWin->pOrderBy;
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
int csrWrite; /* Cursor used to write to eph. table */
|
|
int csrInput = p->pSrc->a[0].iCursor; /* Cursor of sub-select */
|
|
int nInput = p->pSrc->a[0].pTab->nCol; /* Number of cols returned by sub */
|
|
int iInput; /* To iterate through sub cols */
|
|
int addrNe; /* Address of OP_Ne */
|
|
int addrGosubFlush = 0; /* Address of OP_Gosub to flush: */
|
|
int addrInteger = 0; /* Address of OP_Integer */
|
|
int addrEmpty; /* Address of OP_Rewind in flush: */
|
|
int regNew; /* Array of registers holding new input row */
|
|
int regRecord; /* regNew array in record form */
|
|
int regNewPeer = 0; /* Peer values for new row (part of regNew) */
|
|
int regPeer = 0; /* Peer values for current row */
|
|
int regFlushPart = 0; /* Register for "Gosub flush_partition" */
|
|
WindowCodeArg s; /* Context object for sub-routines */
|
|
int lblWhereEnd; /* Label just before sqlite3WhereEnd() code */
|
|
int regStart = 0; /* Value of <expr> PRECEDING */
|
|
int regEnd = 0; /* Value of <expr> FOLLOWING */
|
|
|
|
assert( pMWin->eStart==TK_PRECEDING || pMWin->eStart==TK_CURRENT
|
|
|| pMWin->eStart==TK_FOLLOWING || pMWin->eStart==TK_UNBOUNDED
|
|
);
|
|
assert( pMWin->eEnd==TK_FOLLOWING || pMWin->eEnd==TK_CURRENT
|
|
|| pMWin->eEnd==TK_UNBOUNDED || pMWin->eEnd==TK_PRECEDING
|
|
);
|
|
assert( pMWin->eExclude==0 || pMWin->eExclude==TK_CURRENT
|
|
|| pMWin->eExclude==TK_GROUP || pMWin->eExclude==TK_TIES
|
|
|| pMWin->eExclude==TK_NO
|
|
);
|
|
|
|
lblWhereEnd = sqlite3VdbeMakeLabel(pParse);
|
|
|
|
/* Fill in the context object */
|
|
memset(&s, 0, sizeof(WindowCodeArg));
|
|
s.pParse = pParse;
|
|
s.pMWin = pMWin;
|
|
s.pVdbe = v;
|
|
s.regGosub = regGosub;
|
|
s.addrGosub = addrGosub;
|
|
s.current.csr = pMWin->iEphCsr;
|
|
csrWrite = s.current.csr+1;
|
|
s.start.csr = s.current.csr+2;
|
|
s.end.csr = s.current.csr+3;
|
|
|
|
/* Figure out when rows may be deleted from the ephemeral table. There
|
|
** are four options - they may never be deleted (eDelete==0), they may
|
|
** be deleted as soon as they are no longer part of the window frame
|
|
** (eDelete==WINDOW_AGGINVERSE), they may be deleted as after the row
|
|
** has been returned to the caller (WINDOW_RETURN_ROW), or they may
|
|
** be deleted after they enter the frame (WINDOW_AGGSTEP). */
|
|
switch( pMWin->eStart ){
|
|
case TK_FOLLOWING:
|
|
if( pMWin->eFrmType!=TK_RANGE
|
|
&& windowExprGtZero(pParse, pMWin->pStart)
|
|
){
|
|
s.eDelete = WINDOW_RETURN_ROW;
|
|
}
|
|
break;
|
|
case TK_UNBOUNDED:
|
|
if( windowCacheFrame(pMWin)==0 ){
|
|
if( pMWin->eEnd==TK_PRECEDING ){
|
|
if( pMWin->eFrmType!=TK_RANGE
|
|
&& windowExprGtZero(pParse, pMWin->pEnd)
|
|
){
|
|
s.eDelete = WINDOW_AGGSTEP;
|
|
}
|
|
}else{
|
|
s.eDelete = WINDOW_RETURN_ROW;
|
|
}
|
|
}
|
|
break;
|
|
default:
|
|
s.eDelete = WINDOW_AGGINVERSE;
|
|
break;
|
|
}
|
|
|
|
/* Allocate registers for the array of values from the sub-query, the
|
|
** samve values in record form, and the rowid used to insert said record
|
|
** into the ephemeral table. */
|
|
regNew = pParse->nMem+1;
|
|
pParse->nMem += nInput;
|
|
regRecord = ++pParse->nMem;
|
|
s.regRowid = ++pParse->nMem;
|
|
|
|
/* If the window frame contains an "<expr> PRECEDING" or "<expr> FOLLOWING"
|
|
** clause, allocate registers to store the results of evaluating each
|
|
** <expr>. */
|
|
if( pMWin->eStart==TK_PRECEDING || pMWin->eStart==TK_FOLLOWING ){
|
|
regStart = ++pParse->nMem;
|
|
}
|
|
if( pMWin->eEnd==TK_PRECEDING || pMWin->eEnd==TK_FOLLOWING ){
|
|
regEnd = ++pParse->nMem;
|
|
}
|
|
|
|
/* If this is not a "ROWS BETWEEN ..." frame, then allocate arrays of
|
|
** registers to store copies of the ORDER BY expressions (peer values)
|
|
** for the main loop, and for each cursor (start, current and end). */
|
|
if( pMWin->eFrmType!=TK_ROWS ){
|
|
int nPeer = (pOrderBy ? pOrderBy->nExpr : 0);
|
|
regNewPeer = regNew + pMWin->nBufferCol;
|
|
if( pMWin->pPartition ) regNewPeer += pMWin->pPartition->nExpr;
|
|
regPeer = pParse->nMem+1; pParse->nMem += nPeer;
|
|
s.start.reg = pParse->nMem+1; pParse->nMem += nPeer;
|
|
s.current.reg = pParse->nMem+1; pParse->nMem += nPeer;
|
|
s.end.reg = pParse->nMem+1; pParse->nMem += nPeer;
|
|
}
|
|
|
|
/* Load the column values for the row returned by the sub-select
|
|
** into an array of registers starting at regNew. Assemble them into
|
|
** a record in register regRecord. */
|
|
for(iInput=0; iInput<nInput; iInput++){
|
|
sqlite3VdbeAddOp3(v, OP_Column, csrInput, iInput, regNew+iInput);
|
|
}
|
|
sqlite3VdbeAddOp3(v, OP_MakeRecord, regNew, nInput, regRecord);
|
|
|
|
/* An input row has just been read into an array of registers starting
|
|
** at regNew. If the window has a PARTITION clause, this block generates
|
|
** VM code to check if the input row is the start of a new partition.
|
|
** If so, it does an OP_Gosub to an address to be filled in later. The
|
|
** address of the OP_Gosub is stored in local variable addrGosubFlush. */
|
|
if( pMWin->pPartition ){
|
|
int addr;
|
|
ExprList *pPart = pMWin->pPartition;
|
|
int nPart = pPart->nExpr;
|
|
int regNewPart = regNew + pMWin->nBufferCol;
|
|
KeyInfo *pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pPart, 0, 0);
|
|
|
|
regFlushPart = ++pParse->nMem;
|
|
addr = sqlite3VdbeAddOp3(v, OP_Compare, regNewPart, pMWin->regPart, nPart);
|
|
sqlite3VdbeAppendP4(v, (void*)pKeyInfo, P4_KEYINFO);
|
|
sqlite3VdbeAddOp3(v, OP_Jump, addr+2, addr+4, addr+2);
|
|
VdbeCoverageEqNe(v);
|
|
addrGosubFlush = sqlite3VdbeAddOp1(v, OP_Gosub, regFlushPart);
|
|
VdbeComment((v, "call flush_partition"));
|
|
sqlite3VdbeAddOp3(v, OP_Copy, regNewPart, pMWin->regPart, nPart-1);
|
|
}
|
|
|
|
/* Insert the new row into the ephemeral table */
|
|
sqlite3VdbeAddOp2(v, OP_NewRowid, csrWrite, s.regRowid);
|
|
sqlite3VdbeAddOp3(v, OP_Insert, csrWrite, regRecord, s.regRowid);
|
|
addrNe = sqlite3VdbeAddOp3(v, OP_Ne, pMWin->regOne, 0, s.regRowid);
|
|
VdbeCoverageNeverNull(v);
|
|
|
|
/* This block is run for the first row of each partition */
|
|
s.regArg = windowInitAccum(pParse, pMWin);
|
|
|
|
if( regStart ){
|
|
sqlite3ExprCode(pParse, pMWin->pStart, regStart);
|
|
windowCheckValue(pParse, regStart, 0 + (pMWin->eFrmType==TK_RANGE?3:0));
|
|
}
|
|
if( regEnd ){
|
|
sqlite3ExprCode(pParse, pMWin->pEnd, regEnd);
|
|
windowCheckValue(pParse, regEnd, 1 + (pMWin->eFrmType==TK_RANGE?3:0));
|
|
}
|
|
|
|
if( pMWin->eFrmType!=TK_RANGE && pMWin->eStart==pMWin->eEnd && regStart ){
|
|
int op = ((pMWin->eStart==TK_FOLLOWING) ? OP_Ge : OP_Le);
|
|
int addrGe = sqlite3VdbeAddOp3(v, op, regStart, 0, regEnd);
|
|
VdbeCoverageNeverNullIf(v, op==OP_Ge); /* NeverNull because bound <expr> */
|
|
VdbeCoverageNeverNullIf(v, op==OP_Le); /* values previously checked */
|
|
windowAggFinal(&s, 0);
|
|
sqlite3VdbeAddOp2(v, OP_Rewind, s.current.csr, 1);
|
|
VdbeCoverageNeverTaken(v);
|
|
windowReturnOneRow(&s);
|
|
sqlite3VdbeAddOp1(v, OP_ResetSorter, s.current.csr);
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, lblWhereEnd);
|
|
sqlite3VdbeJumpHere(v, addrGe);
|
|
}
|
|
if( pMWin->eStart==TK_FOLLOWING && pMWin->eFrmType!=TK_RANGE && regEnd ){
|
|
assert( pMWin->eEnd==TK_FOLLOWING );
|
|
sqlite3VdbeAddOp3(v, OP_Subtract, regStart, regEnd, regStart);
|
|
}
|
|
|
|
if( pMWin->eStart!=TK_UNBOUNDED ){
|
|
sqlite3VdbeAddOp2(v, OP_Rewind, s.start.csr, 1);
|
|
VdbeCoverageNeverTaken(v);
|
|
}
|
|
sqlite3VdbeAddOp2(v, OP_Rewind, s.current.csr, 1);
|
|
VdbeCoverageNeverTaken(v);
|
|
sqlite3VdbeAddOp2(v, OP_Rewind, s.end.csr, 1);
|
|
VdbeCoverageNeverTaken(v);
|
|
if( regPeer && pOrderBy ){
|
|
sqlite3VdbeAddOp3(v, OP_Copy, regNewPeer, regPeer, pOrderBy->nExpr-1);
|
|
sqlite3VdbeAddOp3(v, OP_Copy, regPeer, s.start.reg, pOrderBy->nExpr-1);
|
|
sqlite3VdbeAddOp3(v, OP_Copy, regPeer, s.current.reg, pOrderBy->nExpr-1);
|
|
sqlite3VdbeAddOp3(v, OP_Copy, regPeer, s.end.reg, pOrderBy->nExpr-1);
|
|
}
|
|
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, lblWhereEnd);
|
|
|
|
sqlite3VdbeJumpHere(v, addrNe);
|
|
|
|
/* Beginning of the block executed for the second and subsequent rows. */
|
|
if( regPeer ){
|
|
windowIfNewPeer(pParse, pOrderBy, regNewPeer, regPeer, lblWhereEnd);
|
|
}
|
|
if( pMWin->eStart==TK_FOLLOWING ){
|
|
windowCodeOp(&s, WINDOW_AGGSTEP, 0, 0);
|
|
if( pMWin->eEnd!=TK_UNBOUNDED ){
|
|
if( pMWin->eFrmType==TK_RANGE ){
|
|
int lbl = sqlite3VdbeMakeLabel(pParse);
|
|
int addrNext = sqlite3VdbeCurrentAddr(v);
|
|
windowCodeRangeTest(&s, OP_Ge, s.current.csr, regEnd, s.end.csr, lbl);
|
|
windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 0);
|
|
windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrNext);
|
|
sqlite3VdbeResolveLabel(v, lbl);
|
|
}else{
|
|
windowCodeOp(&s, WINDOW_RETURN_ROW, regEnd, 0);
|
|
windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 0);
|
|
}
|
|
}
|
|
}else
|
|
if( pMWin->eEnd==TK_PRECEDING ){
|
|
int bRPS = (pMWin->eStart==TK_PRECEDING && pMWin->eFrmType==TK_RANGE);
|
|
windowCodeOp(&s, WINDOW_AGGSTEP, regEnd, 0);
|
|
if( bRPS ) windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 0);
|
|
windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
|
|
if( !bRPS ) windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 0);
|
|
}else{
|
|
int addr = 0;
|
|
windowCodeOp(&s, WINDOW_AGGSTEP, 0, 0);
|
|
if( pMWin->eEnd!=TK_UNBOUNDED ){
|
|
if( pMWin->eFrmType==TK_RANGE ){
|
|
int lbl = 0;
|
|
addr = sqlite3VdbeCurrentAddr(v);
|
|
if( regEnd ){
|
|
lbl = sqlite3VdbeMakeLabel(pParse);
|
|
windowCodeRangeTest(&s, OP_Ge, s.current.csr, regEnd, s.end.csr, lbl);
|
|
}
|
|
windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
|
|
windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 0);
|
|
if( regEnd ){
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
|
|
sqlite3VdbeResolveLabel(v, lbl);
|
|
}
|
|
}else{
|
|
if( regEnd ){
|
|
addr = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0, 1);
|
|
VdbeCoverage(v);
|
|
}
|
|
windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
|
|
windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 0);
|
|
if( regEnd ) sqlite3VdbeJumpHere(v, addr);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* End of the main input loop */
|
|
sqlite3VdbeResolveLabel(v, lblWhereEnd);
|
|
sqlite3WhereEnd(pWInfo);
|
|
|
|
/* Fall through */
|
|
if( pMWin->pPartition ){
|
|
addrInteger = sqlite3VdbeAddOp2(v, OP_Integer, 0, regFlushPart);
|
|
sqlite3VdbeJumpHere(v, addrGosubFlush);
|
|
}
|
|
|
|
s.regRowid = 0;
|
|
addrEmpty = sqlite3VdbeAddOp1(v, OP_Rewind, csrWrite);
|
|
VdbeCoverage(v);
|
|
if( pMWin->eEnd==TK_PRECEDING ){
|
|
int bRPS = (pMWin->eStart==TK_PRECEDING && pMWin->eFrmType==TK_RANGE);
|
|
windowCodeOp(&s, WINDOW_AGGSTEP, regEnd, 0);
|
|
if( bRPS ) windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 0);
|
|
windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
|
|
}else if( pMWin->eStart==TK_FOLLOWING ){
|
|
int addrStart;
|
|
int addrBreak1;
|
|
int addrBreak2;
|
|
int addrBreak3;
|
|
windowCodeOp(&s, WINDOW_AGGSTEP, 0, 0);
|
|
if( pMWin->eFrmType==TK_RANGE ){
|
|
addrStart = sqlite3VdbeCurrentAddr(v);
|
|
addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 1);
|
|
addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 1);
|
|
}else
|
|
if( pMWin->eEnd==TK_UNBOUNDED ){
|
|
addrStart = sqlite3VdbeCurrentAddr(v);
|
|
addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, regStart, 1);
|
|
addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, 0, 1);
|
|
}else{
|
|
assert( pMWin->eEnd==TK_FOLLOWING );
|
|
addrStart = sqlite3VdbeCurrentAddr(v);
|
|
addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, regEnd, 1);
|
|
addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 1);
|
|
}
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrStart);
|
|
sqlite3VdbeJumpHere(v, addrBreak2);
|
|
addrStart = sqlite3VdbeCurrentAddr(v);
|
|
addrBreak3 = windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 1);
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrStart);
|
|
sqlite3VdbeJumpHere(v, addrBreak1);
|
|
sqlite3VdbeJumpHere(v, addrBreak3);
|
|
}else{
|
|
int addrBreak;
|
|
int addrStart;
|
|
windowCodeOp(&s, WINDOW_AGGSTEP, 0, 0);
|
|
addrStart = sqlite3VdbeCurrentAddr(v);
|
|
addrBreak = windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 1);
|
|
windowCodeOp(&s, WINDOW_AGGINVERSE, regStart, 0);
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrStart);
|
|
sqlite3VdbeJumpHere(v, addrBreak);
|
|
}
|
|
sqlite3VdbeJumpHere(v, addrEmpty);
|
|
|
|
sqlite3VdbeAddOp1(v, OP_ResetSorter, s.current.csr);
|
|
if( pMWin->pPartition ){
|
|
if( pMWin->regStartRowid ){
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, pMWin->regStartRowid);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, pMWin->regEndRowid);
|
|
}
|
|
sqlite3VdbeChangeP1(v, addrInteger, sqlite3VdbeCurrentAddr(v));
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sqlite3VdbeAddOp1(v, OP_Return, regFlushPart);
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|
}
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|
}
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|
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#endif /* SQLITE_OMIT_WINDOWFUNC */
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