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Promote row expressions to full-fledged citizens of the expression syntax,

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rather than allowing them only in a few special cases as before.  In
particular you can now pass a ROW() construct to a function that accepts
a rowtype parameter.  Internal generation of RowExprs fixes a number of
corner cases that used to not work very well, such as referencing the
whole-row result of a JOIN or subquery.  This represents a further step in
the work I started a month or so back to make rowtype values into
first-class citizens.
This commit is contained in:
Tom Lane
2004-05-10 22:44:49 +00:00
parent 9a939886ac
commit 2f63232d30
34 changed files with 1281 additions and 551 deletions
Download Patch File Download Diff File Expand all files Collapse all files

87
src/backend/executor/execQual.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/execQual.c,v 1.158 2004/04/01 21:28:44 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/execQual.c,v 1.159 2004/05/10 22:44:43 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -42,6 +42,7 @@
#include "executor/execdebug.h"
#include "executor/functions.h"
#include "executor/nodeSubplan.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "optimizer/planmain.h"
#include "parser/parse_expr.h"
@@ -93,6 +94,9 @@ static Datum ExecEvalCaseTestExpr(ExprState *exprstate,
static Datum ExecEvalArray(ArrayExprState *astate,
ExprContext *econtext,
bool *isNull, ExprDoneCond *isDone);
static Datum ExecEvalRow(RowExprState *rstate,
ExprContext *econtext,
bool *isNull, ExprDoneCond *isDone);
static Datum ExecEvalCoalesce(CoalesceExprState *coalesceExpr,
ExprContext *econtext,
bool *isNull, ExprDoneCond *isDone);
@@ -2101,6 +2105,54 @@ ExecEvalArray(ArrayExprState *astate, ExprContext *econtext,
return PointerGetDatum(result);
}
/* ----------------------------------------------------------------
* ExecEvalRow - ROW() expressions
* ----------------------------------------------------------------
*/
static Datum
ExecEvalRow(RowExprState *rstate,
ExprContext *econtext,
bool *isNull, ExprDoneCond *isDone)
{
HeapTuple tuple;
Datum *values;
char *nulls;
int nargs;
List *arg;
int i;
/* Set default values for result flags: non-null, not a set result */
*isNull = false;
if (isDone)
*isDone = ExprSingleResult;
/* Allocate workspace */
nargs = length(rstate->args);
if (nargs == 0) /* avoid palloc(0) if no fields */
nargs = 1;
values = (Datum *) palloc(nargs * sizeof(Datum));
nulls = (char *) palloc(nargs * sizeof(char));
/* Evaluate field values */
i = 0;
foreach(arg, rstate->args)
{
ExprState *e = (ExprState *) lfirst(arg);
bool eisnull;
values[i] = ExecEvalExpr(e, econtext, &eisnull, NULL);
nulls[i] = eisnull ? 'n' : ' ';
i++;
}
tuple = heap_formtuple(rstate->tupdesc, values, nulls);
pfree(values);
pfree(nulls);
return HeapTupleGetDatum(tuple);
}
/* ----------------------------------------------------------------
* ExecEvalCoalesce
* ----------------------------------------------------------------
@@ -2822,6 +2874,39 @@ ExecInitExpr(Expr *node, PlanState *parent)
state = (ExprState *) astate;
}
break;
case T_RowExpr:
{
RowExpr *rowexpr = (RowExpr *) node;
RowExprState *rstate = makeNode(RowExprState);
List *outlist;
List *inlist;
rstate->xprstate.evalfunc = (ExprStateEvalFunc) ExecEvalRow;
outlist = NIL;
foreach(inlist, rowexpr->args)
{
Expr *e = (Expr *) lfirst(inlist);
ExprState *estate;
estate = ExecInitExpr(e, parent);
outlist = lappend(outlist, estate);
}
rstate->args = outlist;
/* Build tupdesc to describe result tuples */
if (rowexpr->row_typeid == RECORDOID)
{
/* generic record, use runtime type assignment */
rstate->tupdesc = ExecTypeFromExprList(rowexpr->args);
rstate->tupdesc = BlessTupleDesc(rstate->tupdesc);
}
else
{
/* it's been cast to a named type, use that */
rstate->tupdesc = lookup_rowtype_tupdesc(rowexpr->row_typeid, -1);
}
state = (ExprState *) rstate;
}
break;
case T_CoalesceExpr:
{
CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;

36
src/backend/executor/execTuples.c
View File

@@ -15,7 +15,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/execTuples.c,v 1.76 2004/04/01 21:28:44 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/execTuples.c,v 1.77 2004/05/10 22:44:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -111,6 +111,7 @@
#include "access/heapam.h"
#include "catalog/pg_type.h"
#include "executor/executor.h"
#include "parser/parse_expr.h"
#include "utils/lsyscache.h"
#include "utils/typcache.h"
@@ -118,6 +119,7 @@
static TupleDesc ExecTypeFromTLInternal(List *targetList,
bool hasoid, bool skipjunk);
/* ----------------------------------------------------------------
* tuple table create/delete functions
* ----------------------------------------------------------------
@@ -595,6 +597,38 @@ ExecTypeFromTLInternal(List *targetList, bool hasoid, bool skipjunk)
return typeInfo;
}
/*
* ExecTypeFromExprList - build a tuple descriptor from a list of Exprs
*
* Here we must make up an arbitrary set of field names.
*/
TupleDesc
ExecTypeFromExprList(List *exprList)
{
TupleDesc typeInfo;
List *l;
int cur_resno = 1;
char fldname[NAMEDATALEN];
typeInfo = CreateTemplateTupleDesc(length(exprList), false);
foreach(l, exprList)
{
Node *e = lfirst(l);
sprintf(fldname, "f%d", cur_resno);
TupleDescInitEntry(typeInfo,
cur_resno++,
fldname,
exprType(e),
exprTypmod(e),
0);
}
return typeInfo;
}
/*
* BlessTupleDesc - make a completed tuple descriptor useful for SRFs
*

20
src/backend/nodes/copyfuncs.c
View File

@@ -15,7 +15,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.280 2004/05/05 04:48:45 tgl Exp $
* $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.281 2004/05/10 22:44:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -998,6 +998,21 @@ _copyArrayExpr(ArrayExpr *from)
return newnode;
}
/*
* _copyRowExpr
*/
static RowExpr *
_copyRowExpr(RowExpr *from)
{
RowExpr *newnode = makeNode(RowExpr);
COPY_NODE_FIELD(args);
COPY_SCALAR_FIELD(row_typeid);
COPY_SCALAR_FIELD(row_format);
return newnode;
}
/*
* _copyCoalesceExpr
*/
@@ -2674,6 +2689,9 @@ copyObject(void *from)
case T_ArrayExpr:
retval = _copyArrayExpr(from);
break;
case T_RowExpr:
retval = _copyRowExpr(from);
break;
case T_CoalesceExpr:
retval = _copyCoalesceExpr(from);
break;

23
src/backend/nodes/equalfuncs.c
View File

@@ -18,7 +18,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/equalfuncs.c,v 1.219 2004/05/05 04:48:45 tgl Exp $
* $PostgreSQL: pgsql/src/backend/nodes/equalfuncs.c,v 1.220 2004/05/10 22:44:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -423,6 +423,24 @@ _equalArrayExpr(ArrayExpr *a, ArrayExpr *b)
return true;
}
static bool
_equalRowExpr(RowExpr *a, RowExpr *b)
{
COMPARE_NODE_FIELD(args);
COMPARE_SCALAR_FIELD(row_typeid);
/*
* Special-case COERCE_DONTCARE, so that planner can build coercion
* nodes that are equal() to both explicit and implicit coercions.
*/
if (a->row_format != b->row_format &&
a->row_format != COERCE_DONTCARE &&
b->row_format != COERCE_DONTCARE)
return false;
return true;
}
static bool
_equalCoalesceExpr(CoalesceExpr *a, CoalesceExpr *b)
{
@@ -1748,6 +1766,9 @@ equal(void *a, void *b)
case T_ArrayExpr:
retval = _equalArrayExpr(a, b);
break;
case T_RowExpr:
retval = _equalRowExpr(a, b);
break;
case T_CoalesceExpr:
retval = _equalCoalesceExpr(a, b);
break;

14
src/backend/nodes/makefuncs.c
View File

@@ -9,12 +9,13 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/makefuncs.c,v 1.42 2003/11/29 19:51:49 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/nodes/makefuncs.c,v 1.43 2004/05/10 22:44:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
#include "utils/lsyscache.h"
@@ -170,6 +171,17 @@ makeNullConst(Oid consttype)
typByVal);
}
/*
* makeBoolConst -
* creates a Const node representing a boolean value (can be NULL too)
*/
Node *
makeBoolConst(bool value, bool isnull)
{
/* note that pg_type.h hardwires size of bool as 1 ... duplicate it */
return (Node *) makeConst(BOOLOID, 1, BoolGetDatum(value), isnull, true);
}
/*
* makeBoolExpr -
* creates a BoolExpr node

15
src/backend/nodes/outfuncs.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.235 2004/05/08 21:21:18 tgl Exp $
* $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.236 2004/05/10 22:44:44 tgl Exp $
*
* NOTES
* Every node type that can appear in stored rules' parsetrees *must*
@@ -828,6 +828,16 @@ _outArrayExpr(StringInfo str, ArrayExpr *node)
WRITE_BOOL_FIELD(multidims);
}
static void
_outRowExpr(StringInfo str, RowExpr *node)
{
WRITE_NODE_TYPE("ROW");
WRITE_NODE_FIELD(args);
WRITE_OID_FIELD(row_typeid);
WRITE_ENUM_FIELD(row_format, CoercionForm);
}
static void
_outCoalesceExpr(StringInfo str, CoalesceExpr *node)
{
@@ -1719,6 +1729,9 @@ _outNode(StringInfo str, void *obj)
case T_ArrayExpr:
_outArrayExpr(str, obj);
break;
case T_RowExpr:
_outRowExpr(str, obj);
break;
case T_CoalesceExpr:
_outCoalesceExpr(str, obj);
break;

19
src/backend/nodes/readfuncs.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/nodes/readfuncs.c,v 1.168 2004/05/08 21:21:18 tgl Exp $
* $PostgreSQL: pgsql/src/backend/nodes/readfuncs.c,v 1.169 2004/05/10 22:44:44 tgl Exp $
*
* NOTES
* Path and Plan nodes do not have any readfuncs support, because we
@@ -628,6 +628,21 @@ _readArrayExpr(void)
READ_DONE();
}
/*
* _readRowExpr
*/
static RowExpr *
_readRowExpr(void)
{
READ_LOCALS(RowExpr);
READ_NODE_FIELD(args);
READ_OID_FIELD(row_typeid);
READ_ENUM_FIELD(row_format, CoercionForm);
READ_DONE();
}
/*
* _readCoalesceExpr
*/
@@ -978,6 +993,8 @@ parseNodeString(void)
return_value = _readCaseTestExpr();
else if (MATCH("ARRAY", 5))
return_value = _readArrayExpr();
else if (MATCH("ROW", 3))
return_value = _readRowExpr();
else if (MATCH("COALESCE", 8))
return_value = _readCoalesceExpr();
else if (MATCH("NULLIFEXPR", 10))

27
src/backend/optimizer/path/allpaths.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.113 2004/04/25 18:23:56 neilc Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.114 2004/05/10 22:44:44 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -57,9 +57,10 @@ static void compare_tlist_datatypes(List *tlist, List *colTypes,
bool *differentTypes);
static bool qual_is_pushdown_safe(Query *subquery, Index rti, Node *qual,
bool *differentTypes);
static void subquery_push_qual(Query *subquery, Index rti, Node *qual);
static void subquery_push_qual(Query *subquery,
RangeTblEntry *rte, Index rti, Node *qual);
static void recurse_push_qual(Node *setOp, Query *topquery,
Index rti, Node *qual);
RangeTblEntry *rte, Index rti, Node *qual);
/*
@@ -375,7 +376,7 @@ set_subquery_pathlist(Query *root, RelOptInfo *rel,
if (qual_is_pushdown_safe(subquery, rti, clause, differentTypes))
{
/* Push it down */
subquery_push_qual(subquery, rti, clause);
subquery_push_qual(subquery, rte, rti, clause);
}
else
{
@@ -778,12 +779,12 @@ qual_is_pushdown_safe(Query *subquery, Index rti, Node *qual,
* subquery_push_qual - push down a qual that we have determined is safe
*/
static void
subquery_push_qual(Query *subquery, Index rti, Node *qual)
subquery_push_qual(Query *subquery, RangeTblEntry *rte, Index rti, Node *qual)
{
if (subquery->setOperations != NULL)
{
/* Recurse to push it separately to each component query */
recurse_push_qual(subquery->setOperations, subquery, rti, qual);
recurse_push_qual(subquery->setOperations, subquery, rte, rti, qual);
}
else
{
@@ -797,7 +798,7 @@ subquery_push_qual(Query *subquery, Index rti, Node *qual)
* This step also ensures that when we are pushing into a setop tree,
* each component query gets its own copy of the qual.
*/
qual = ResolveNew(qual, rti, 0,
qual = ResolveNew(qual, rti, 0, rte,
subquery->targetList,
CMD_SELECT, 0);
subquery->havingQual = make_and_qual(subquery->havingQual,
@@ -816,23 +817,23 @@ subquery_push_qual(Query *subquery, Index rti, Node *qual)
*/
static void
recurse_push_qual(Node *setOp, Query *topquery,
Index rti, Node *qual)
RangeTblEntry *rte, Index rti, Node *qual)
{
if (IsA(setOp, RangeTblRef))
{
RangeTblRef *rtr = (RangeTblRef *) setOp;
RangeTblEntry *rte = rt_fetch(rtr->rtindex, topquery->rtable);
Query *subquery = rte->subquery;
RangeTblEntry *subrte = rt_fetch(rtr->rtindex, topquery->rtable);
Query *subquery = subrte->subquery;
Assert(subquery != NULL);
subquery_push_qual(subquery, rti, qual);
subquery_push_qual(subquery, rte, rti, qual);
}
else if (IsA(setOp, SetOperationStmt))
{
SetOperationStmt *op = (SetOperationStmt *) setOp;
recurse_push_qual(op->larg, topquery, rti, qual);
recurse_push_qual(op->rarg, topquery, rti, qual);
recurse_push_qual(op->larg, topquery, rte, rti, qual);
recurse_push_qual(op->rarg, topquery, rte, rti, qual);
}
else
{

9
src/backend/optimizer/path/clausesel.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/path/clausesel.c,v 1.64 2004/01/05 16:44:40 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/path/clausesel.c,v 1.65 2004/05/10 22:44:45 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -27,11 +27,6 @@
#include "utils/selfuncs.h"
/* note that pg_type.h hardwires size of bool as 1 ... duplicate it */
#define MAKEBOOLCONST(val,isnull) \
((Node *) makeConst(BOOLOID, 1, (Datum) (val), (isnull), true))
/*
* Data structure for accumulating info about possible range-query
* clause pairs in clauselist_selectivity.
@@ -486,7 +481,7 @@ clause_selectivity(Query *root,
s1 = restriction_selectivity(root,
BooleanEqualOperator,
makeList2(var,
MAKEBOOLCONST(true,
makeBoolConst(true,
false)),
varRelid);
}

50
src/backend/optimizer/prep/prepjointree.c
View File

@@ -16,7 +16,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.16 2004/01/10 18:13:53 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.17 2004/05/10 22:44:45 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -45,7 +45,8 @@ typedef struct reduce_outer_joins_state
static bool is_simple_subquery(Query *subquery);
static bool has_nullable_targetlist(Query *subquery);
static void resolvenew_in_jointree(Node *jtnode, int varno, List *subtlist);
static void resolvenew_in_jointree(Node *jtnode, int varno,
RangeTblEntry *rte, List *subtlist);
static reduce_outer_joins_state *reduce_outer_joins_pass1(Node *jtnode);
static void reduce_outer_joins_pass2(Node *jtnode,
reduce_outer_joins_state *state,
@@ -154,14 +155,10 @@ pull_up_subqueries(Query *parse, Node *jtnode, bool below_outer_join)
* such expressions; we'd have to figure out how to get the pseudo-
* variables evaluated at the right place in the modified plan
* tree. Fix it someday.
*
* Note: even if the subquery itself is simple enough, we can't pull
* it up if there is a reference to its whole tuple result.
* Perhaps a pseudo-variable is the answer here too.
*/
if (rte->rtekind == RTE_SUBQUERY && is_simple_subquery(subquery) &&
(!below_outer_join || has_nullable_targetlist(subquery)) &&
!contain_whole_tuple_var((Node *) parse, varno, 0))
if (rte->rtekind == RTE_SUBQUERY &&
is_simple_subquery(subquery) &&
(!below_outer_join || has_nullable_targetlist(subquery)))
{
int rtoffset;
List *subtlist;
@@ -206,8 +203,7 @@ pull_up_subqueries(Query *parse, Node *jtnode, bool below_outer_join)
* the one above.
*/
if (is_simple_subquery(subquery) &&
(!below_outer_join || has_nullable_targetlist(subquery)) &&
!contain_whole_tuple_var((Node *) parse, varno, 0))
(!below_outer_join || has_nullable_targetlist(subquery)))
{
/* good to go */
}
@@ -247,24 +243,25 @@ pull_up_subqueries(Query *parse, Node *jtnode, bool below_outer_join)
subtlist = subquery->targetList;
parse->targetList = (List *)
ResolveNew((Node *) parse->targetList,
varno, 0, subtlist, CMD_SELECT, 0);
resolvenew_in_jointree((Node *) parse->jointree, varno, subtlist);
varno, 0, rte, subtlist, CMD_SELECT, 0);
resolvenew_in_jointree((Node *) parse->jointree, varno,
rte, subtlist);
Assert(parse->setOperations == NULL);
parse->havingQual =
ResolveNew(parse->havingQual,
varno, 0, subtlist, CMD_SELECT, 0);
varno, 0, rte, subtlist, CMD_SELECT, 0);
parse->in_info_list = (List *)
ResolveNew((Node *) parse->in_info_list,
varno, 0, subtlist, CMD_SELECT, 0);
varno, 0, rte, subtlist, CMD_SELECT, 0);
foreach(rt, parse->rtable)
{
RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt);
RangeTblEntry *otherrte = (RangeTblEntry *) lfirst(rt);
if (rte->rtekind == RTE_JOIN)
rte->joinaliasvars = (List *)
ResolveNew((Node *) rte->joinaliasvars,
varno, 0, subtlist, CMD_SELECT, 0);
if (otherrte->rtekind == RTE_JOIN)
otherrte->joinaliasvars = (List *)
ResolveNew((Node *) otherrte->joinaliasvars,
varno, 0, rte, subtlist, CMD_SELECT, 0);
}
/*
@@ -479,7 +476,8 @@ has_nullable_targetlist(Query *subquery)
* but there's no other way...
*/
static void
resolvenew_in_jointree(Node *jtnode, int varno, List *subtlist)
resolvenew_in_jointree(Node *jtnode, int varno,
RangeTblEntry *rte, List *subtlist)
{
if (jtnode == NULL)
return;
@@ -493,18 +491,18 @@ resolvenew_in_jointree(Node *jtnode, int varno, List *subtlist)
List *l;
foreach(l, f->fromlist)
resolvenew_in_jointree(lfirst(l), varno, subtlist);
resolvenew_in_jointree(lfirst(l), varno, rte, subtlist);
f->quals = ResolveNew(f->quals,
varno, 0, subtlist, CMD_SELECT, 0);
varno, 0, rte, subtlist, CMD_SELECT, 0);
}
else if (IsA(jtnode, JoinExpr))
{
JoinExpr *j = (JoinExpr *) jtnode;
resolvenew_in_jointree(j->larg, varno, subtlist);
resolvenew_in_jointree(j->rarg, varno, subtlist);
resolvenew_in_jointree(j->larg, varno, rte, subtlist);
resolvenew_in_jointree(j->rarg, varno, rte, subtlist);
j->quals = ResolveNew(j->quals,
varno, 0, subtlist, CMD_SELECT, 0);
varno, 0, rte, subtlist, CMD_SELECT, 0);
/*
* We don't bother to update the colvars list, since it won't be

109
src/backend/optimizer/util/clauses.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.169 2004/04/02 23:14:08 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.170 2004/05/10 22:44:45 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@@ -41,10 +41,6 @@
#include "utils/syscache.h"
/* note that pg_type.h hardwires size of bool as 1 ... duplicate it */
#define MAKEBOOLCONST(val,isnull) \
((Node *) makeConst(BOOLOID, 1, (Datum) (val), (isnull), true))
typedef struct
{
int nargs;
@@ -281,7 +277,7 @@ Expr *
make_ands_explicit(List *andclauses)
{
if (andclauses == NIL)
return (Expr *) MAKEBOOLCONST(true, false);
return (Expr *) makeBoolConst(true, false);
else if (lnext(andclauses) == NIL)
return (Expr *) lfirst(andclauses);
else
@@ -484,6 +480,8 @@ expression_returns_set_walker(Node *node, void *context)
return false;
if (IsA(node, ArrayExpr))
return false;
if (IsA(node, RowExpr))
return false;
if (IsA(node, CoalesceExpr))
return false;
if (IsA(node, NullIfExpr))
@@ -778,6 +776,8 @@ contain_nonstrict_functions_walker(Node *node, void *context)
if (IsA(node, CaseWhen))
return true;
/* NB: ArrayExpr might someday be nonstrict */
if (IsA(node, RowExpr))
return true;
if (IsA(node, CoalesceExpr))
return true;
if (IsA(node, NullIfExpr))
@@ -1030,6 +1030,8 @@ set_coercionform_dontcare_walker(Node *node, void *context)
((FuncExpr *) node)->funcformat = COERCE_DONTCARE;
if (IsA(node, RelabelType))
((RelabelType *) node)->relabelformat = COERCE_DONTCARE;
if (IsA(node, RowExpr))
((RowExpr *) node)->row_format = COERCE_DONTCARE;
if (IsA(node, CoerceToDomain))
((CoerceToDomain *) node)->coercionformat = COERCE_DONTCARE;
return expression_tree_walker(node, set_coercionform_dontcare_walker,
@@ -1197,11 +1199,11 @@ eval_const_expressions_mutator(Node *node, List *active_fns)
{
/* all nulls? then not distinct */
if (all_null_input)
return MAKEBOOLCONST(false, false);
return makeBoolConst(false, false);
/* one null? then distinct */
if (has_null_input)
return MAKEBOOLCONST(true, false);
return makeBoolConst(true, false);
/* otherwise try to evaluate the '=' operator */
/* (NOT okay to try to inline it, though!) */
@@ -1272,12 +1274,12 @@ eval_const_expressions_mutator(Node *node, List *active_fns)
newargs = simplify_or_arguments(args,
&haveNull, &forceTrue);
if (forceTrue)
return MAKEBOOLCONST(true, false);
return makeBoolConst(true, false);
if (haveNull)
newargs = lappend(newargs, MAKEBOOLCONST(false, true));
newargs = lappend(newargs, makeBoolConst(false, true));
/* If all the inputs are FALSE, result is FALSE */
if (newargs == NIL)
return MAKEBOOLCONST(false, false);
return makeBoolConst(false, false);
/* If only one nonconst-or-NULL input, it's the result */
if (lnext(newargs) == NIL)
return (Node *) lfirst(newargs);
@@ -1293,12 +1295,12 @@ eval_const_expressions_mutator(Node *node, List *active_fns)
newargs = simplify_and_arguments(args,
&haveNull, &forceFalse);
if (forceFalse)
return MAKEBOOLCONST(false, false);
return makeBoolConst(false, false);
if (haveNull)
newargs = lappend(newargs, MAKEBOOLCONST(false, true));
newargs = lappend(newargs, makeBoolConst(false, true));
/* If all the inputs are TRUE, result is TRUE */
if (newargs == NIL)
return MAKEBOOLCONST(true, false);
return makeBoolConst(true, false);
/* If only one nonconst-or-NULL input, it's the result */
if (lnext(newargs) == NIL)
return (Node *) lfirst(newargs);
@@ -1313,9 +1315,9 @@ eval_const_expressions_mutator(Node *node, List *active_fns)
/* NOT NULL => NULL */
if (const_input->constisnull)
return MAKEBOOLCONST(false, true);
return makeBoolConst(false, true);
/* otherwise pretty easy */
return MAKEBOOLCONST(!DatumGetBool(const_input->constvalue),
return makeBoolConst(!DatumGetBool(const_input->constvalue),
false);
}
else if (not_clause((Node *) lfirst(args)))
@@ -1387,7 +1389,6 @@ eval_const_expressions_mutator(Node *node, List *active_fns)
}
if (IsA(node, CaseExpr))
{
/*----------
* CASE expressions can be simplified if there are constant
* condition clauses:
@@ -1546,22 +1547,38 @@ eval_const_expressions_mutator(Node *node, List *active_fns)
* We can optimize field selection from a whole-row Var into a
* simple Var. (This case won't be generated directly by the
* parser, because ParseComplexProjection short-circuits it. But
* it can arise while simplifying functions.) If the argument
* isn't a whole-row Var, just fall through to do generic
* processing.
* it can arise while simplifying functions.) Also, we can
* optimize field selection from a RowExpr construct.
*/
FieldSelect *fselect = (FieldSelect *) node;
Var *argvar = (Var *) fselect->arg;
FieldSelect *newfselect;
Node *arg;
if (argvar && IsA(argvar, Var) &&
argvar->varattno == InvalidAttrNumber)
arg = eval_const_expressions_mutator((Node *) fselect->arg,
active_fns);
if (arg && IsA(arg, Var) &&
((Var *) arg)->varattno == InvalidAttrNumber)
{
return (Node *) makeVar(argvar->varno,
return (Node *) makeVar(((Var *) arg)->varno,
fselect->fieldnum,
fselect->resulttype,
fselect->resulttypmod,
argvar->varlevelsup);
((Var *) arg)->varlevelsup);
}
if (arg && IsA(arg, RowExpr))
{
RowExpr *rowexpr = (RowExpr *) arg;
if (fselect->fieldnum > 0 &&
fselect->fieldnum <= length(rowexpr->args))
return (Node *) nth(fselect->fieldnum - 1, rowexpr->args);
}
newfselect = makeNode(FieldSelect);
newfselect->arg = (Expr *) arg;
newfselect->fieldnum = fselect->fieldnum;
newfselect->resulttype = fselect->resulttype;
newfselect->resulttypmod = fselect->resulttypmod;
return (Node *) newfselect;
}
/*
@@ -1759,7 +1776,6 @@ evaluate_function(Oid funcid, Oid result_type, List *args,
bool has_null_input = false;
List *arg;
FuncExpr *newexpr;
char result_typtype;
/*
* Can't simplify if it returns a set.
@@ -1796,15 +1812,6 @@ evaluate_function(Oid funcid, Oid result_type, List *args,
has_nonconst_input)
return NULL;
/*
* Can't simplify functions returning composite types (mainly because
* datumCopy() doesn't cope; FIXME someday when we have a saner
* representation for whole-tuple results).
*/
result_typtype = get_typtype(funcform->prorettype);
if (result_typtype == 'c')
return NULL;
/*
* OK, looks like we can simplify this operator/function.
*
@@ -1850,7 +1857,6 @@ inline_function(Oid funcid, Oid result_type, List *args,
HeapTuple func_tuple, List *active_fns)
{
Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
char result_typtype;
bool polymorphic = false;
Oid argtypes[FUNC_MAX_ARGS];
char *src;
@@ -1877,21 +1883,6 @@ inline_function(Oid funcid, Oid result_type, List *args,
funcform->pronargs != length(args))
return NULL;
/*
* Forget it if declared return type is not base, domain, or
* polymorphic
*/
result_typtype = get_typtype(funcform->prorettype);
if (result_typtype != 'b' &&
result_typtype != 'd')
{
if (funcform->prorettype == ANYARRAYOID ||
funcform->prorettype == ANYELEMENTOID)
polymorphic = true;
else
return NULL;
}
/* Check for recursive function, and give up trying to expand if so */
if (oidMember(funcid, active_fns))
return NULL;
@@ -1912,6 +1903,10 @@ inline_function(Oid funcid, Oid result_type, List *args,
}
}
if (funcform->prorettype == ANYARRAYOID ||
funcform->prorettype == ANYELEMENTOID)
polymorphic = true;
/*
* Setup error traceback support for ereport(). This is so that we
* can finger the function that bad information came from.
@@ -2483,6 +2478,8 @@ expression_tree_walker(Node *node,
break;
case T_ArrayExpr:
return walker(((ArrayExpr *) node)->elements, context);
case T_RowExpr:
return walker(((RowExpr *) node)->args, context);
case T_CoalesceExpr:
return walker(((CoalesceExpr *) node)->args, context);
case T_NullIfExpr:
@@ -2889,6 +2886,16 @@ expression_tree_mutator(Node *node,
return (Node *) newnode;
}
break;
case T_RowExpr:
{
RowExpr *rowexpr = (RowExpr *) node;
RowExpr *newnode;
FLATCOPY(newnode, rowexpr, RowExpr);
MUTATE(newnode->args, rowexpr->args, List *);
return (Node *) newnode;
}
break;
case T_CoalesceExpr:
{
CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;

53
src/backend/optimizer/util/var.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/util/var.c,v 1.55 2003/11/29 19:51:51 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/util/var.c,v 1.56 2004/05/10 22:44:45 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -191,19 +191,6 @@ contain_var_reference_walker(Node *node,
}
/*
* contain_whole_tuple_var
*
* Detect whether a parsetree contains any references to the whole
* tuple of a given rtable entry (ie, a Var with varattno = 0).
*/
bool
contain_whole_tuple_var(Node *node, int varno, int levelsup)
{
return contain_var_reference(node, varno, InvalidAttrNumber, levelsup);
}
/*
* contain_var_clause
* Recursively scan a clause to discover whether it contains any Var nodes
@@ -486,7 +473,10 @@ pull_var_clause_walker(Node *node, pull_var_clause_context *context)
* flatten_join_alias_vars
* Replace Vars that reference JOIN outputs with references to the original
* relation variables instead. This allows quals involving such vars to be
* pushed down.
* pushed down. Whole-row Vars that reference JOIN relations are expanded
* into RowExpr constructs that name the individual output Vars. This
* is necessary since we will not scan the JOIN as a base relation, which
* is the only way that the executor can directly handle whole-row Vars.
*
* NOTE: this is used on not-yet-planned expressions. We do not expect it
* to be applied directly to a Query node.
@@ -520,8 +510,39 @@ flatten_join_alias_vars_mutator(Node *node,
rte = rt_fetch(var->varno, context->root->rtable);
if (rte->rtekind != RTE_JOIN)
return node;
if (var->varattno == InvalidAttrNumber)
{
/* Must expand whole-row reference */
RowExpr *rowexpr;
List *fields = NIL;
List *l;
foreach(l, rte->joinaliasvars)
{
newvar = (Node *) lfirst(l);
/*
* If we are expanding an alias carried down from an upper
* query, must adjust its varlevelsup fields.
*/
if (context->sublevels_up != 0)
{
newvar = copyObject(newvar);
IncrementVarSublevelsUp(newvar, context->sublevels_up, 0);
}
/* Recurse in case join input is itself a join */
newvar = flatten_join_alias_vars_mutator(newvar, context);
fields = lappend(fields, newvar);
}
rowexpr = makeNode(RowExpr);
rowexpr->args = fields;
rowexpr->row_typeid = var->vartype;
rowexpr->row_format = COERCE_IMPLICIT_CAST;
return (Node *) rowexpr;
}
/* Expand join alias reference */
Assert(var->varattno > 0);
/* Okay, must expand it */
newvar = (Node *) nth(var->varattno - 1, rte->joinaliasvars);
/*

462
src/backend/parser/gram.y
View File

@@ -11,7 +11,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.453 2004/05/05 04:48:46 tgl Exp $
* $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.454 2004/05/10 22:44:45 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@@ -80,11 +80,9 @@ static Node *makeStringConst(char *str, TypeName *typename);
static Node *makeIntConst(int val);
static Node *makeFloatConst(char *str);
static Node *makeAConst(Value *v);
static Node *makeRowExpr(List *opr, List *largs, List *rargs);
static Node *makeDistinctExpr(List *largs, List *rargs);
static Node *makeRowNullTest(NullTestType test, List *args);
static Node *makeRowNullTest(NullTestType test, RowExpr *row);
static DefElem *makeDefElem(char *name, Node *arg);
static A_Const *makeBoolConst(bool state);
static A_Const *makeBoolAConst(bool state);
static FuncCall *makeOverlaps(List *largs, List *rargs);
static List *extractArgTypes(List *parameters);
static SelectStmt *findLeftmostSelect(SelectStmt *node);
@@ -277,9 +275,9 @@ static void doNegateFloat(Value *v);
%type <node> columnDef
%type <defelt> def_elem
%type <node> def_arg columnElem where_clause insert_column_item
a_expr b_expr c_expr r_expr AexprConst
a_expr b_expr c_expr AexprConst
in_expr having_clause func_table array_expr
%type <list> row row_descriptor type_list array_expr_list
%type <list> row type_list array_expr_list
%type <node> case_expr case_arg when_clause case_default
%type <list> when_clause_list
%type <ival> sub_type
@@ -5710,163 +5708,6 @@ opt_interval:
*
*****************************************************************************/
/* Expressions using row descriptors
* Define row_descriptor to allow yacc to break the reduce/reduce conflict
* with singleton expressions. Use SQL99's ROW keyword to allow rows of
* one element.
*/
r_expr: row IN_P select_with_parens
{
SubLink *n = makeNode(SubLink);
n->subLinkType = ANY_SUBLINK;
n->lefthand = $1;
n->operName = makeList1(makeString("="));
n->subselect = $3;
$$ = (Node *)n;
}
| row NOT IN_P select_with_parens
{
/* Make an IN node */
SubLink *n = makeNode(SubLink);
n->subLinkType = ANY_SUBLINK;
n->lefthand = $1;
n->operName = makeList1(makeString("="));
n->subselect = $4;
/* Stick a NOT on top */
$$ = (Node *) makeA_Expr(AEXPR_NOT, NIL, NULL, (Node *) n);
}
| row subquery_Op sub_type select_with_parens
%prec Op
{
SubLink *n = makeNode(SubLink);
n->subLinkType = $3;
n->lefthand = $1;
n->operName = $2;
n->subselect = $4;
$$ = (Node *)n;
}
| row subquery_Op select_with_parens
%prec Op
{
SubLink *n = makeNode(SubLink);
n->subLinkType = MULTIEXPR_SUBLINK;
n->lefthand = $1;
n->operName = $2;
n->subselect = $3;
$$ = (Node *)n;
}
| row subquery_Op row
%prec Op
{
$$ = makeRowExpr($2, $1, $3);
}
| row IS NULL_P
{
$$ = makeRowNullTest(IS_NULL, $1);
}
| row IS NOT NULL_P
{
$$ = makeRowNullTest(IS_NOT_NULL, $1);
}
| row OVERLAPS row
{
$$ = (Node *)makeOverlaps($1, $3);
}
| row IS DISTINCT FROM row
%prec IS
{
/* IS DISTINCT FROM has the following rules for non-array types:
* a) the row lengths must be equal
* b) if both rows are zero-length, then they are not distinct
* c) if any element is distinct, the rows are distinct
* The rules for an element being distinct:
* a) if the elements are both NULL, then they are not distinct
* b) if the elements compare to be equal, then they are not distinct
* c) otherwise, they are distinct
*/
List *largs = $1;
List *rargs = $5;
/* lengths don't match? then complain */
if (length(largs) != length(rargs))
{
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("unequal number of entries in row expression")));
}
/* both are zero-length rows? then they are not distinct */
else if (length(largs) <= 0)
{
$$ = (Node *)makeBoolConst(FALSE);
}
/* otherwise, we need to compare each element */
else
{
$$ = (Node *)makeDistinctExpr(largs, rargs);
}
}
;
/* Explicit row production.
* SQL99 allows an optional ROW keyword, so we can now do single-element productions
* without conflicting with the parenthesized a_expr production.
*/
row: ROW '(' row_descriptor ')' { $$ = $3; }
| ROW '(' a_expr ')' { $$ = makeList1($3); }
| ROW '(' ')' { $$ = NULL; }
| '(' row_descriptor ')' { $$ = $2; }
;
row_descriptor: expr_list ',' a_expr { $$ = lappend($1, $3); }
;
sub_type: ANY { $$ = ANY_SUBLINK; }
| SOME { $$ = ANY_SUBLINK; }
| ALL { $$ = ALL_SUBLINK; }
;
all_Op: Op { $$ = $1; }
| MathOp { $$ = $1; }
;
MathOp: '+' { $$ = "+"; }
| '-' { $$ = "-"; }
| '*' { $$ = "*"; }
| '/' { $$ = "/"; }
| '%' { $$ = "%"; }
| '^' { $$ = "^"; }
| '<' { $$ = "<"; }
| '>' { $$ = ">"; }
| '=' { $$ = "="; }
;
qual_Op: Op
{ $$ = makeList1(makeString($1)); }
| OPERATOR '(' any_operator ')' { $$ = $3; }
;
qual_all_Op:
all_Op
{ $$ = makeList1(makeString($1)); }
| OPERATOR '(' any_operator ')' { $$ = $3; }
;
subquery_Op:
all_Op { $$ = makeList1(makeString($1)); }
| OPERATOR '(' any_operator ')' { $$ = $3; }
| LIKE { $$ = makeList1(makeString("~~")); }
| NOT LIKE { $$ = makeList1(makeString("!~~")); }
| ILIKE { $$ = makeList1(makeString("~~*")); }
| NOT ILIKE { $$ = makeList1(makeString("!~~*")); }
/* cannot put SIMILAR TO here, because SIMILAR TO is a hack.
* the regular expression is preprocessed by a function (similar_escape),
* and the ~ operator for posix regular expressions is used.
* x SIMILAR TO y -> x ~ similar_escape(y)
* this transformation is made on the fly by the parser upwards.
* however the SubLink structure which handles any/some/all stuff
* is not ready for such a thing.
*/
;
/*
* General expressions
* This is the heart of the expression syntax.
@@ -6046,31 +5887,55 @@ a_expr: c_expr { $$ = $1; }
*/
| a_expr ISNULL
{
NullTest *n = makeNode(NullTest);
n->arg = (Expr *) $1;
n->nulltesttype = IS_NULL;
$$ = (Node *)n;
if (IsA($1, RowExpr))
$$ = makeRowNullTest(IS_NULL, (RowExpr *) $1);
else
{
NullTest *n = makeNode(NullTest);
n->arg = (Expr *) $1;
n->nulltesttype = IS_NULL;
$$ = (Node *)n;
}
}
| a_expr IS NULL_P
{
NullTest *n = makeNode(NullTest);
n->arg = (Expr *) $1;
n->nulltesttype = IS_NULL;
$$ = (Node *)n;
if (IsA($1, RowExpr))
$$ = makeRowNullTest(IS_NULL, (RowExpr *) $1);
else
{
NullTest *n = makeNode(NullTest);
n->arg = (Expr *) $1;
n->nulltesttype = IS_NULL;
$$ = (Node *)n;
}
}
| a_expr NOTNULL
{
NullTest *n = makeNode(NullTest);
n->arg = (Expr *) $1;
n->nulltesttype = IS_NOT_NULL;
$$ = (Node *)n;
if (IsA($1, RowExpr))
$$ = makeRowNullTest(IS_NOT_NULL, (RowExpr *) $1);
else
{
NullTest *n = makeNode(NullTest);
n->arg = (Expr *) $1;
n->nulltesttype = IS_NOT_NULL;
$$ = (Node *)n;
}
}
| a_expr IS NOT NULL_P
{
NullTest *n = makeNode(NullTest);
n->arg = (Expr *) $1;
n->nulltesttype = IS_NOT_NULL;
$$ = (Node *)n;
if (IsA($1, RowExpr))
$$ = makeRowNullTest(IS_NOT_NULL, (RowExpr *) $1);
else
{
NullTest *n = makeNode(NullTest);
n->arg = (Expr *) $1;
n->nulltesttype = IS_NOT_NULL;
$$ = (Node *)n;
}
}
| row OVERLAPS row
{
$$ = (Node *)makeOverlaps($1, $3);
}
| a_expr IS TRUE_P
{
@@ -6115,7 +5980,9 @@ a_expr: c_expr { $$ = $1; }
$$ = (Node *)b;
}
| a_expr IS DISTINCT FROM a_expr %prec IS
{ $$ = (Node *) makeSimpleA_Expr(AEXPR_DISTINCT, "=", $1, $5); }
{
$$ = (Node *) makeSimpleA_Expr(AEXPR_DISTINCT, "=", $1, $5);
}
| a_expr IS OF '(' type_list ')' %prec IS
{
$$ = (Node *) makeSimpleA_Expr(AEXPR_OF, "=", $1, (Node *) $5);
@@ -6143,7 +6010,10 @@ a_expr: c_expr { $$ = $1; }
{
SubLink *n = (SubLink *)$3;
n->subLinkType = ANY_SUBLINK;
n->lefthand = makeList1($1);
if (IsA($1, RowExpr))
n->lefthand = ((RowExpr *) $1)->args;
else
n->lefthand = makeList1($1);
n->operName = makeList1(makeString("="));
$$ = (Node *)n;
}
@@ -6171,7 +6041,10 @@ a_expr: c_expr { $$ = $1; }
/* Make an IN node */
SubLink *n = (SubLink *)$4;
n->subLinkType = ANY_SUBLINK;
n->lefthand = makeList1($1);
if (IsA($1, RowExpr))
n->lefthand = ((RowExpr *) $1)->args;
else
n->lefthand = makeList1($1);
n->operName = makeList1(makeString("="));
/* Stick a NOT on top */
$$ = (Node *) makeA_Expr(AEXPR_NOT, NIL, NULL, (Node *) n);
@@ -6196,7 +6069,10 @@ a_expr: c_expr { $$ = $1; }
{
SubLink *n = makeNode(SubLink);
n->subLinkType = $3;
n->lefthand = makeList1($1);
if (IsA($1, RowExpr))
n->lefthand = ((RowExpr *) $1)->args;
else
n->lefthand = makeList1($1);
n->operName = $2;
n->subselect = $4;
$$ = (Node *)n;
@@ -6223,8 +6099,6 @@ a_expr: c_expr { $$ = $1; }
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("UNIQUE predicate is not yet implemented")));
}
| r_expr
{ $$ = $1; }
;
/*
@@ -6277,7 +6151,9 @@ b_expr: c_expr
| b_expr qual_Op %prec POSTFIXOP
{ $$ = (Node *) makeA_Expr(AEXPR_OP, $2, $1, NULL); }
| b_expr IS DISTINCT FROM b_expr %prec IS
{ $$ = (Node *) makeSimpleA_Expr(AEXPR_DISTINCT, "=", $1, $5); }
{
$$ = (Node *) makeSimpleA_Expr(AEXPR_DISTINCT, "=", $1, $5);
}
| b_expr IS OF '(' type_list ')' %prec IS
{
$$ = (Node *) makeSimpleA_Expr(AEXPR_OF, "=", $1, (Node *) $5);
@@ -6819,12 +6695,86 @@ c_expr: columnref { $$ = (Node *) $1; }
}
| ARRAY array_expr
{ $$ = $2; }
| row
{
RowExpr *r = makeNode(RowExpr);
r->args = $1;
r->row_typeid = InvalidOid; /* not analyzed yet */
$$ = (Node *)r;
}
;
/*
* Supporting nonterminals for expressions.
*/
/* Explicit row production.
*
* SQL99 allows an optional ROW keyword, so we can now do single-element rows
* without conflicting with the parenthesized a_expr production. Without the
* ROW keyword, there must be more than one a_expr inside the parens.
*/
row: ROW '(' expr_list ')' { $$ = $3; }
| ROW '(' ')' { $$ = NIL; }
| '(' expr_list ',' a_expr ')' { $$ = lappend($2, $4); }
;
sub_type: ANY { $$ = ANY_SUBLINK; }
| SOME { $$ = ANY_SUBLINK; }
| ALL { $$ = ALL_SUBLINK; }
;
all_Op: Op { $$ = $1; }
| MathOp { $$ = $1; }
;
MathOp: '+' { $$ = "+"; }
| '-' { $$ = "-"; }
| '*' { $$ = "*"; }
| '/' { $$ = "/"; }
| '%' { $$ = "%"; }
| '^' { $$ = "^"; }
| '<' { $$ = "<"; }
| '>' { $$ = ">"; }
| '=' { $$ = "="; }
;
qual_Op: Op
{ $$ = makeList1(makeString($1)); }
| OPERATOR '(' any_operator ')'
{ $$ = $3; }
;
qual_all_Op:
all_Op
{ $$ = makeList1(makeString($1)); }
| OPERATOR '(' any_operator ')'
{ $$ = $3; }
;
subquery_Op:
all_Op
{ $$ = makeList1(makeString($1)); }
| OPERATOR '(' any_operator ')'
{ $$ = $3; }
| LIKE
{ $$ = makeList1(makeString("~~")); }
| NOT LIKE
{ $$ = makeList1(makeString("!~~")); }
| ILIKE
{ $$ = makeList1(makeString("~~*")); }
| NOT ILIKE
{ $$ = makeList1(makeString("!~~*")); }
/* cannot put SIMILAR TO here, because SIMILAR TO is a hack.
* the regular expression is preprocessed by a function (similar_escape),
* and the ~ operator for posix regular expressions is used.
* x SIMILAR TO y -> x ~ similar_escape(y)
* this transformation is made on the fly by the parser upwards.
* however the SubLink structure which handles any/some/all stuff
* is not ready for such a thing.
*/
;
opt_indirection:
opt_indirection '[' a_expr ']'
{
@@ -7358,11 +7308,11 @@ AexprConst: Iconst
}
| TRUE_P
{
$$ = (Node *)makeBoolConst(TRUE);
$$ = (Node *)makeBoolAConst(TRUE);
}
| FALSE_P
{
$$ = (Node *)makeBoolConst(FALSE);
$$ = (Node *)makeBoolAConst(FALSE);
}
| NULL_P
{
@@ -7892,11 +7842,11 @@ makeDefElem(char *name, Node *arg)
return f;
}
/* makeBoolConst()
/* makeBoolAConst()
* Create an A_Const node and initialize to a boolean constant.
*/
static A_Const *
makeBoolConst(bool state)
makeBoolAConst(bool state)
{
A_Const *n = makeNode(A_Const);
n->val.type = T_String;
@@ -7905,119 +7855,41 @@ makeBoolConst(bool state)
return n;
}
/* makeRowExpr()
* Generate separate operator nodes for a single row descriptor expression.
* Perhaps this should go deeper in the parser someday...
* - thomas 1997-12-22
*/
static Node *
makeRowExpr(List *opr, List *largs, List *rargs)
{
Node *expr = NULL;
Node *larg, *rarg;
char *oprname;
if (length(largs) != length(rargs))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("unequal number of entries in row expression")));
if (lnext(largs) != NIL)
expr = makeRowExpr(opr, lnext(largs), lnext(rargs));
larg = lfirst(largs);
rarg = lfirst(rargs);
oprname = strVal(llast(opr));
if ((strcmp(oprname, "=") == 0) ||
(strcmp(oprname, "<") == 0) ||
(strcmp(oprname, "<=") == 0) ||
(strcmp(oprname, ">") == 0) ||
(strcmp(oprname, ">=") == 0))
{
if (expr == NULL)
expr = (Node *) makeA_Expr(AEXPR_OP, opr, larg, rarg);
else
expr = (Node *) makeA_Expr(AEXPR_AND, NIL, expr,
(Node *) makeA_Expr(AEXPR_OP, opr,
larg, rarg));
}
else if (strcmp(oprname, "<>") == 0)
{
if (expr == NULL)
expr = (Node *) makeA_Expr(AEXPR_OP, opr, larg, rarg);
else
expr = (Node *) makeA_Expr(AEXPR_OR, NIL, expr,
(Node *) makeA_Expr(AEXPR_OP, opr,
larg, rarg));
}
else
{
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("operator %s is not supported for row expressions",
oprname)));
}
return expr;
}
/* makeDistinctExpr()
* Generate separate operator nodes for a single row descriptor expression.
* Same comments as for makeRowExpr().
*/
static Node *
makeDistinctExpr(List *largs, List *rargs)
{
Node *expr = NULL;
Node *larg, *rarg;
if (length(largs) != length(rargs))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("unequal number of entries in row expression")));
if (lnext(largs) != NIL)
expr = makeDistinctExpr(lnext(largs), lnext(rargs));
larg = lfirst(largs);
rarg = lfirst(rargs);
if (expr == NULL)
expr = (Node *) makeSimpleA_Expr(AEXPR_DISTINCT, "=", larg, rarg);
else
expr = (Node *) makeA_Expr(AEXPR_OR, NIL, expr,
(Node *) makeSimpleA_Expr(AEXPR_DISTINCT, "=",
larg, rarg));
return expr;
}
/* makeRowNullTest()
* Generate separate operator nodes for a single row descriptor test.
*
* Eventually this should be eliminated in favor of making the NullTest
* node type capable of handling it directly.
*/
static Node *
makeRowNullTest(NullTestType test, List *args)
makeRowNullTest(NullTestType test, RowExpr *row)
{
Node *expr = NULL;
NullTest *n;
Node *result = NULL;
List *arg;
if (lnext(args) != NIL)
expr = makeRowNullTest(test, lnext(args));
foreach(arg, row->args)
{
NullTest *n;
n = makeNode(NullTest);
n->arg = (Expr *) lfirst(args);
n->nulltesttype = test;
n = makeNode(NullTest);
n->arg = (Expr *) lfirst(arg);
n->nulltesttype = test;
if (expr == NULL)
expr = (Node *) n;
else if (test == IS_NOT_NULL)
expr = (Node *) makeA_Expr(AEXPR_OR, NIL, expr, (Node *)n);
else
expr = (Node *) makeA_Expr(AEXPR_AND, NIL, expr, (Node *)n);
if (result == NULL)
result = (Node *) n;
else if (test == IS_NOT_NULL)
result = (Node *) makeA_Expr(AEXPR_OR, NIL, result, (Node *)n);
else
result = (Node *) makeA_Expr(AEXPR_AND, NIL, result, (Node *)n);
}
return expr;
if (result == NULL)
{
/* zero-length rows? Generate constant TRUE or FALSE */
result = (Node *) makeBoolAConst(test == IS_NULL);
}
return result;
}
/* makeOverlaps()

121
src/backend/parser/parse_coerce.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.114 2004/03/15 01:13:40 tgl Exp $
* $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.115 2004/05/10 22:44:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -19,19 +19,26 @@
#include "nodes/makefuncs.h"
#include "nodes/params.h"
#include "optimizer/clauses.h"
#include "parser/parsetree.h"
#include "parser/parse_coerce.h"
#include "parser/parse_expr.h"
#include "parser/parse_func.h"
#include "parser/parse_relation.h"
#include "parser/parse_type.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"
#include "utils/typcache.h"
static Node *coerce_type_typmod(Node *node,
Oid targetTypeId, int32 targetTypMod,
CoercionForm cformat, bool isExplicit);
static Node *coerce_record_to_complex(ParseState *pstate, Node *node,
Oid targetTypeId,
CoercionContext ccontext,
CoercionForm cformat);
/*
@@ -279,6 +286,13 @@ coerce_type(ParseState *pstate, Node *node,
}
return result;
}
if (inputTypeId == RECORDOID &&
ISCOMPLEX(targetTypeId))
{
/* Coerce a RECORD to a specific complex type */
return coerce_record_to_complex(pstate, node, targetTypeId,
ccontext, cformat);
}
if (typeInheritsFrom(inputTypeId, targetTypeId))
{
/*
@@ -359,6 +373,14 @@ can_coerce_type(int nargs, Oid *input_typeids, Oid *target_typeids,
&funcId))
continue;
/*
* If input is RECORD and target is a composite type, assume
* we can coerce (may need tighter checking here)
*/
if (inputTypeId == RECORDOID &&
ISCOMPLEX(targetTypeId))
continue;
/*
* If input is a class type that inherits from target, accept
*/
@@ -506,6 +528,103 @@ coerce_type_typmod(Node *node, Oid targetTypeId, int32 targetTypMod,
return node;
}
/*
* coerce_record_to_complex
* Coerce a RECORD to a specific composite type.
*
* Currently we only support this for inputs that are RowExprs or whole-row
* Vars.
*/
static Node *
coerce_record_to_complex(ParseState *pstate, Node *node,
Oid targetTypeId,
CoercionContext ccontext,
CoercionForm cformat)
{
RowExpr *rowexpr;
TupleDesc tupdesc;
List *args = NIL;
List *newargs;
int i;
List *arg;
if (node && IsA(node, RowExpr))
{
args = ((RowExpr *) node)->args;
}
else if (node && IsA(node, Var) &&
((Var *) node)->varattno == InvalidAttrNumber)
{
RangeTblEntry *rte;
AttrNumber nfields;
AttrNumber nf;
rte = GetRTEByRangeTablePosn(pstate,
((Var *) node)->varno,
((Var *) node)->varlevelsup);
nfields = length(rte->eref->colnames);
for (nf = 1; nf <= nfields; nf++)
{
Oid vartype;
int32 vartypmod;
get_rte_attribute_type(rte, nf, &vartype, &vartypmod);
args = lappend(args,
makeVar(((Var *) node)->varno,
nf,
vartype,
vartypmod,
((Var *) node)->varlevelsup));
}
}
else
ereport(ERROR,
(errcode(ERRCODE_CANNOT_COERCE),
errmsg("cannot cast type %s to %s",
format_type_be(RECORDOID),
format_type_be(targetTypeId))));
tupdesc = lookup_rowtype_tupdesc(targetTypeId, -1);
if (length(args) != tupdesc->natts)
ereport(ERROR,
(errcode(ERRCODE_CANNOT_COERCE),
errmsg("cannot cast type %s to %s",
format_type_be(RECORDOID),
format_type_be(targetTypeId)),
errdetail("Input has wrong number of columns.")));
newargs = NIL;
i = 0;
foreach(arg, args)
{
Node *expr = (Node *) lfirst(arg);
Oid exprtype = exprType(expr);
expr = coerce_to_target_type(pstate,
expr, exprtype,
tupdesc->attrs[i]->atttypid,
tupdesc->attrs[i]->atttypmod,
ccontext,
COERCE_IMPLICIT_CAST);
if (expr == NULL)
ereport(ERROR,
(errcode(ERRCODE_CANNOT_COERCE),
errmsg("cannot cast type %s to %s",
format_type_be(RECORDOID),
format_type_be(targetTypeId)),
errdetail("Cannot cast type %s to %s in column %d.",
format_type_be(exprtype),
format_type_be(tupdesc->attrs[i]->atttypid),
i + 1)));
newargs = lappend(newargs, expr);
i++;
}
rowexpr = makeNode(RowExpr);
rowexpr->args = newargs;
rowexpr->row_typeid = targetTypeId;
rowexpr->row_format = cformat;
return (Node *) rowexpr;
}
/* coerce_to_boolean()
* Coerce an argument of a construct that requires boolean input

304
src/backend/parser/parse_expr.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/parser/parse_expr.c,v 1.169 2004/04/18 18:12:58 tgl Exp $
* $PostgreSQL: pgsql/src/backend/parser/parse_expr.c,v 1.170 2004/05/10 22:44:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -37,13 +37,19 @@
bool Transform_null_equals = false;
static Node *typecast_expression(ParseState *pstate, Node *expr,
TypeName *typename);
static Node *transformColumnRef(ParseState *pstate, ColumnRef *cref);
static Node *transformWholeRowRef(ParseState *pstate, char *schemaname,
char *relname);
static Node *transformIndirection(ParseState *pstate, Node *basenode,
List *indirection);
static Node *typecast_expression(ParseState *pstate, Node *expr,
TypeName *typename);
static Node *make_row_op(ParseState *pstate, List *opname,
Node *ltree, Node *rtree);
static Node *make_row_distinct_op(ParseState *pstate, List *opname,
Node *ltree, Node *rtree);
static Expr *make_distinct_op(ParseState *pstate, List *opname,
Node *ltree, Node *rtree);
/*
@@ -202,6 +208,9 @@ transformExpr(ParseState *pstate, Node *expr)
{
case AEXPR_OP:
{
Node *lexpr = a->lexpr;
Node *rexpr = a->rexpr;
/*
* Special-case "foo = NULL" and "NULL = foo"
* for compatibility with standards-broken
@@ -211,27 +220,51 @@ transformExpr(ParseState *pstate, Node *expr)
if (Transform_null_equals &&
length(a->name) == 1 &&
strcmp(strVal(lfirst(a->name)), "=") == 0 &&
(exprIsNullConstant(a->lexpr) ||
exprIsNullConstant(a->rexpr)))
(exprIsNullConstant(lexpr) ||
exprIsNullConstant(rexpr)))
{
NullTest *n = makeNode(NullTest);
n->nulltesttype = IS_NULL;
if (exprIsNullConstant(a->lexpr))
n->arg = (Expr *) a->rexpr;
if (exprIsNullConstant(lexpr))
n->arg = (Expr *) rexpr;
else
n->arg = (Expr *) a->lexpr;
n->arg = (Expr *) lexpr;
result = transformExpr(pstate,
(Node *) n);
}
else if (lexpr && IsA(lexpr, RowExpr) &&
rexpr && IsA(rexpr, SubLink) &&
((SubLink *) rexpr)->subLinkType == EXPR_SUBLINK)
{
/*
* Convert "row op subselect" into a
* MULTIEXPR sublink. Formerly the grammar
* did this, but now that a row construct is
* allowed anywhere in expressions, it's
* easier to do it here.
*/
SubLink *s = (SubLink *) rexpr;
s->subLinkType = MULTIEXPR_SUBLINK;
s->lefthand = ((RowExpr *) lexpr)->args;
s->operName = a->name;
result = transformExpr(pstate, (Node *) s);
}
else if (lexpr && IsA(lexpr, RowExpr) &&
rexpr && IsA(rexpr, RowExpr))
{
/* "row op row" */
result = make_row_op(pstate, a->name,
lexpr, rexpr);
}
else
{
Node *lexpr = transformExpr(pstate,
a->lexpr);
Node *rexpr = transformExpr(pstate,
a->rexpr);
/* Ordinary scalar operator */
lexpr = transformExpr(pstate, lexpr);
rexpr = transformExpr(pstate, rexpr);
result = (Node *) make_op(pstate,
a->name,
@@ -311,25 +344,27 @@ transformExpr(ParseState *pstate, Node *expr)
break;
case AEXPR_DISTINCT:
{
Node *lexpr = transformExpr(pstate,
a->lexpr);
Node *rexpr = transformExpr(pstate,
a->rexpr);
Node *lexpr = a->lexpr;
Node *rexpr = a->rexpr;
result = (Node *) make_op(pstate,
a->name,
lexpr,
rexpr);
if (((OpExpr *) result)->opresulttype != BOOLOID)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("IS DISTINCT FROM requires = operator to yield boolean")));
if (lexpr && IsA(lexpr, RowExpr) &&
rexpr && IsA(rexpr, RowExpr))
{
/* "row op row" */
result = make_row_distinct_op(pstate, a->name,
lexpr, rexpr);
}
else
{
/* Ordinary scalar operator */
lexpr = transformExpr(pstate, lexpr);
rexpr = transformExpr(pstate, rexpr);
/*
* We rely on DistinctExpr and OpExpr being
* same struct
*/
NodeSetTag(result, T_DistinctExpr);
result = (Node *) make_distinct_op(pstate,
a->name,
lexpr,
rexpr);
}
}
break;
case AEXPR_NULLIF:
@@ -787,6 +822,32 @@ transformExpr(ParseState *pstate, Node *expr)
break;
}
case T_RowExpr:
{
RowExpr *r = (RowExpr *) expr;
RowExpr *newr = makeNode(RowExpr);
List *newargs = NIL;
List *arg;
/* Transform the field expressions */
foreach(arg, r->args)
{
Node *e = (Node *) lfirst(arg);
Node *newe;
newe = transformExpr(pstate, e);
newargs = lappend(newargs, newe);
}
newr->args = newargs;
/* Barring later casting, we consider the type RECORD */
newr->row_typeid = RECORDOID;
newr->row_format = COERCE_IMPLICIT_CAST;
result = (Node *) newr;
break;
}
case T_CoalesceExpr:
{
CoalesceExpr *c = (CoalesceExpr *) expr;
@@ -1113,14 +1174,11 @@ transformColumnRef(ParseState *pstate, ColumnRef *cref)
/*
* Construct a whole-row reference to represent the notation "relation.*".
*
* In simple cases, this will be a Var with varno set to the correct range
* A whole-row reference is a Var with varno set to the correct range
* table entry, and varattno == 0 to signal that it references the whole
* tuple. (Use of zero here is unclean, since it could easily be confused
* with error cases, but it's not worth changing now.) The vartype indicates
* a rowtype; either a named composite type, or RECORD.
*
* We also need the ability to build a row-constructor expression, but the
* infrastructure for that doesn't exist just yet.
*/
static Node *
transformWholeRowRef(ParseState *pstate, char *schemaname, char *relname)
@@ -1185,12 +1243,10 @@ transformWholeRowRef(ParseState *pstate, char *schemaname, char *relname)
break;
default:
/*
* RTE is a join or subselect. For the moment we represent this
* as a whole-row Var of RECORD type, but this will not actually
* work; need a row-constructor expression instead.
*
* XXX after fixing, be sure that unknown_attribute still
* does the right thing.
* RTE is a join or subselect. We represent this as a whole-row
* Var of RECORD type. (Note that in most cases the Var will
* be expanded to a RowExpr during planning, but that is not
* our concern here.)
*/
result = (Node *) makeVar(vnum,
InvalidAttrNumber,
@@ -1266,8 +1322,8 @@ exprType(Node *expr)
if (sublink->subLinkType == EXPR_SUBLINK)
type = tent->resdom->restype;
else
/* ARRAY_SUBLINK */
{
/* ARRAY_SUBLINK */
type = get_array_type(tent->resdom->restype);
if (!OidIsValid(type))
ereport(ERROR,
@@ -1305,8 +1361,8 @@ exprType(Node *expr)
if (subplan->subLinkType == EXPR_SUBLINK)
type = tent->resdom->restype;
else
/* ARRAY_SUBLINK */
{
/* ARRAY_SUBLINK */
type = get_array_type(tent->resdom->restype);
if (!OidIsValid(type))
ereport(ERROR,
@@ -1340,6 +1396,9 @@ exprType(Node *expr)
case T_ArrayExpr:
type = ((ArrayExpr *) expr)->array_typeid;
break;
case T_RowExpr:
type = ((RowExpr *) expr)->row_typeid;
break;
case T_CoalesceExpr:
type = ((CoalesceExpr *) expr)->coalescetype;
break;
@@ -1573,3 +1632,166 @@ typecast_expression(ParseState *pstate, Node *expr, TypeName *typename)
return expr;
}
/*
* Transform a "row op row" construct
*/
static Node *
make_row_op(ParseState *pstate, List *opname, Node *ltree, Node *rtree)
{
Node *result = NULL;
RowExpr *lrow,
*rrow;
List *largs,
*rargs;
List *largl,
*rargl;
char *oprname;
BoolExprType boolop;
/* Inputs are untransformed RowExprs */
lrow = (RowExpr *) transformExpr(pstate, ltree);
rrow = (RowExpr *) transformExpr(pstate, rtree);
Assert(IsA(lrow, RowExpr));
Assert(IsA(rrow, RowExpr));
largs = lrow->args;
rargs = rrow->args;
if (length(largs) != length(rargs))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("unequal number of entries in row expression")));
/*
* XXX it's really wrong to generate a simple AND combination for < <=
* > >=. We probably need to invent a new runtime node type to handle
* those correctly. For the moment, though, keep on doing this ...
*/
oprname = strVal(llast(opname));
if ((strcmp(oprname, "=") == 0) ||
(strcmp(oprname, "<") == 0) ||
(strcmp(oprname, "<=") == 0) ||
(strcmp(oprname, ">") == 0) ||
(strcmp(oprname, ">=") == 0))
{
boolop = AND_EXPR;
}
else if (strcmp(oprname, "<>") == 0)
{
boolop = OR_EXPR;
}
else
{
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("operator %s is not supported for row expressions",
oprname)));
boolop = 0; /* keep compiler quiet */
}
/* XXX use forboth */
rargl = rargs;
foreach(largl, largs)
{
Node *larg = (Node *) lfirst(largl);
Node *rarg = (Node *) lfirst(rargl);
Node *cmp;
rargl = lnext(rargl);
cmp = (Node *) make_op(pstate, opname, larg, rarg);
cmp = coerce_to_boolean(pstate, cmp, "row comparison");
if (result == NULL)
result = cmp;
else
result = (Node *) makeBoolExpr(boolop,
makeList2(result, cmp));
}
if (result == NULL)
{
/* zero-length rows? Generate constant TRUE or FALSE */
if (boolop == AND_EXPR)
result = makeBoolConst(true, false);
else
result = makeBoolConst(false, false);
}
return result;
}
/*
* Transform a "row IS DISTINCT FROM row" construct
*/
static Node *
make_row_distinct_op(ParseState *pstate, List *opname,
Node *ltree, Node *rtree)
{
Node *result = NULL;
RowExpr *lrow,
*rrow;
List *largs,
*rargs;
List *largl,
*rargl;
/* Inputs are untransformed RowExprs */
lrow = (RowExpr *) transformExpr(pstate, ltree);
rrow = (RowExpr *) transformExpr(pstate, rtree);
Assert(IsA(lrow, RowExpr));
Assert(IsA(rrow, RowExpr));
largs = lrow->args;
rargs = rrow->args;
if (length(largs) != length(rargs))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("unequal number of entries in row expression")));
/* XXX use forboth */
rargl = rargs;
foreach(largl, largs)
{
Node *larg = (Node *) lfirst(largl);
Node *rarg = (Node *) lfirst(rargl);
Node *cmp;
rargl = lnext(rargl);
cmp = (Node *) make_distinct_op(pstate, opname, larg, rarg);
if (result == NULL)
result = cmp;
else
result = (Node *) makeBoolExpr(OR_EXPR,
makeList2(result, cmp));
}
if (result == NULL)
{
/* zero-length rows? Generate constant FALSE */
result = makeBoolConst(false, false);
}
return result;
}
/*
* make the node for an IS DISTINCT FROM operator
*/
static Expr *
make_distinct_op(ParseState *pstate, List *opname, Node *ltree, Node *rtree)
{
Expr *result;
result = make_op(pstate, opname, ltree, rtree);
if (((OpExpr *) result)->opresulttype != BOOLOID)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("IS DISTINCT FROM requires = operator to yield boolean")));
/*
* We rely on DistinctExpr and OpExpr being
* same struct
*/
NodeSetTag(result, T_DistinctExpr);
return result;
}

6
src/backend/parser/parse_target.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/parser/parse_target.c,v 1.116 2004/04/02 19:06:58 tgl Exp $
* $PostgreSQL: pgsql/src/backend/parser/parse_target.c,v 1.117 2004/05/10 22:44:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -643,6 +643,10 @@ FigureColnameInternal(Node *node, char **name)
/* make ARRAY[] act like a function */
*name = "array";
return 2;
case T_RowExpr:
/* make ROW() act like a function */
*name = "row";
return 2;
case T_CoalesceExpr:
/* make coalesce() act like a regular function */
*name = "coalesce";

5
src/backend/rewrite/rewriteHandler.c
View File

@@ -7,7 +7,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/rewrite/rewriteHandler.c,v 1.134 2004/04/01 21:28:44 tgl Exp $
* $PostgreSQL: pgsql/src/backend/rewrite/rewriteHandler.c,v 1.135 2004/05/10 22:44:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -212,6 +212,8 @@ rewriteRuleAction(Query *parsetree,
sub_action = (Query *) ResolveNew((Node *) sub_action,
new_varno,
0,
rt_fetch(new_varno,
sub_action->rtable),
parsetree->targetList,
event,
current_varno);
@@ -947,6 +949,7 @@ CopyAndAddInvertedQual(Query *parsetree,
new_qual = ResolveNew(new_qual,
PRS2_NEW_VARNO,
0,
rt_fetch(rt_index, parsetree->rtable),
parsetree->targetList,
event,
rt_index);

114
src/backend/rewrite/rewriteManip.c
View File

@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/rewrite/rewriteManip.c,v 1.81 2003/11/29 19:51:55 pgsql Exp $
* $PostgreSQL: pgsql/src/backend/rewrite/rewriteManip.c,v 1.82 2004/05/10 22:44:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -850,6 +850,10 @@ AddInvertedQual(Query *parsetree, Node *qual)
* If not, we either change the unmatched Var's varno to update_varno
* (when event == CMD_UPDATE) or replace it with a constant NULL.
*
* The caller must also provide target_rte, the RTE describing the target
* relation. This is needed to handle whole-row Vars referencing the target.
* We expand such Vars into RowExpr constructs.
*
* Note: the business with inserted_sublink is needed to update hasSubLinks
* in subqueries when the replacement adds a subquery inside a subquery.
* Messy, isn't it? We do not need to do similar pushups for hasAggs,
@@ -861,12 +865,52 @@ typedef struct
{
int target_varno;
int sublevels_up;
RangeTblEntry *target_rte;
List *targetlist;
int event;
int update_varno;
bool inserted_sublink;
} ResolveNew_context;
static Node *
resolve_one_var(Var *var, ResolveNew_context *context)
{
TargetEntry *tle;
tle = get_tle_by_resno(context->targetlist, var->varattno);
if (tle == NULL)
{
/* Failed to find column in insert/update tlist */
if (context->event == CMD_UPDATE)
{
/* For update, just change unmatched var's varno */
var = (Var *) copyObject(var);
var->varno = context->update_varno;
var->varnoold = context->update_varno;
return (Node *) var;
}
else
{
/* Otherwise replace unmatched var with a null */
return (Node *) makeNullConst(var->vartype);
}
}
else
{
/* Make a copy of the tlist item to return */
Node *n = copyObject(tle->expr);
/* Adjust varlevelsup if tlist item is from higher query */
if (var->varlevelsup > 0)
IncrementVarSublevelsUp(n, var->varlevelsup, 0);
/* Report it if we are adding a sublink to query */
if (!context->inserted_sublink)
context->inserted_sublink = checkExprHasSubLink(n);
return n;
}
}
static Node *
ResolveNew_mutator(Node *node, ResolveNew_context *context)
{
@@ -881,45 +925,41 @@ ResolveNew_mutator(Node *node, ResolveNew_context *context)
if (this_varno == context->target_varno &&
this_varlevelsup == context->sublevels_up)
{
TargetEntry *tle;
/* band-aid: don't do the wrong thing with a whole-tuple Var */
if (var->varattno == InvalidAttrNumber)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot handle whole-row reference")));
tle = get_tle_by_resno(context->targetlist, var->varattno);
if (tle == NULL)
{
if (context->event == CMD_UPDATE)
{
/* For update, just change unmatched var's varno */
var = (Var *) copyObject(node);
var->varno = context->update_varno;
var->varnoold = context->update_varno;
return (Node *) var;
}
else
{
/* Otherwise replace unmatched var with a null */
return (Node *) makeNullConst(var->vartype);
}
}
else
{
/* Make a copy of the tlist item to return */
Node *n = copyObject(tle->expr);
/* Must expand whole-tuple reference into RowExpr */
RangeTblEntry *rte = context->target_rte;
RowExpr *rowexpr;
List *fields = NIL;
AttrNumber nfields = length(rte->eref->colnames);
AttrNumber nf;
/* Adjust varlevelsup if tlist item is from higher query */
if (this_varlevelsup > 0)
IncrementVarSublevelsUp(n, this_varlevelsup, 0);
/* Report it if we are adding a sublink to query */
if (!context->inserted_sublink)
context->inserted_sublink = checkExprHasSubLink(n);
return n;
for (nf = 1; nf <= nfields; nf++)
{
Oid vartype;
int32 vartypmod;
Var *newvar;
get_rte_attribute_type(rte, nf, &vartype, &vartypmod);
newvar = makeVar(this_varno,
nf,
vartype,
vartypmod,
this_varlevelsup);
fields = lappend(fields,
resolve_one_var(newvar, context));
}
rowexpr = makeNode(RowExpr);
rowexpr->args = fields;
rowexpr->row_typeid = var->vartype;
rowexpr->row_format = COERCE_IMPLICIT_CAST;
return (Node *) rowexpr;
}
/* Normal case for scalar variable */
return resolve_one_var(var, context);
}
/* otherwise fall through to copy the var normally */
}
@@ -948,12 +988,14 @@ ResolveNew_mutator(Node *node, ResolveNew_context *context)
Node *
ResolveNew(Node *node, int target_varno, int sublevels_up,
RangeTblEntry *target_rte,
List *targetlist, int event, int update_varno)
{
ResolveNew_context context;
context.target_varno = target_varno;
context.sublevels_up = sublevels_up;
context.target_rte = target_rte;
context.targetlist = targetlist;
context.event = event;
context.update_varno = update_varno;

38
src/backend/utils/adt/ruleutils.c
View File

@@ -3,7 +3,7 @@
* back to source text
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.165 2004/05/07 03:19:44 tgl Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.166 2004/05/10 22:44:46 tgl Exp $
*
* This software is copyrighted by Jan Wieck - Hamburg.
*
@@ -2432,6 +2432,7 @@ isSimpleNode(Node *node, Node *parentNode, int prettyFlags)
case T_ArrayRef:
case T_ArrayExpr:
case T_RowExpr:
case T_CoalesceExpr:
case T_NullIfExpr:
case T_Aggref:
@@ -2528,6 +2529,7 @@ isSimpleNode(Node *node, Node *parentNode, int prettyFlags)
case T_BoolExpr: /* lower precedence */
case T_ArrayRef: /* other separators */
case T_ArrayExpr: /* other separators */
case T_RowExpr: /* other separators */
case T_CoalesceExpr: /* own parentheses */
case T_NullIfExpr: /* other separators */
case T_Aggref: /* own parentheses */
@@ -2574,6 +2576,7 @@ isSimpleNode(Node *node, Node *parentNode, int prettyFlags)
}
case T_ArrayRef: /* other separators */
case T_ArrayExpr: /* other separators */
case T_RowExpr: /* other separators */
case T_CoalesceExpr: /* own parentheses */
case T_NullIfExpr: /* other separators */
case T_Aggref: /* own parentheses */
@@ -2942,11 +2945,9 @@ get_rule_expr(Node *node, deparse_context *context,
* arg.fieldname, but most cases where FieldSelect is used
* are *not* simple. So, always use parenthesized syntax.
*/
if (!PRETTY_PAREN(context))
appendStringInfoChar(buf, '(');
appendStringInfoChar(buf, '(');
get_rule_expr_paren((Node *) fselect->arg, context, true, node);
if (!PRETTY_PAREN(context))
appendStringInfoChar(buf, ')');
appendStringInfoChar(buf, ')');
appendStringInfo(buf, ".%s", quote_identifier(fieldname));
}
break;
@@ -3051,6 +3052,33 @@ get_rule_expr(Node *node, deparse_context *context,
}
break;
case T_RowExpr:
{
RowExpr *rowexpr = (RowExpr *) node;
List *arg;
char *sep;
/*
* SQL99 allows "ROW" to be omitted when length(args) > 1,
* but for simplicity we always print it.
*/
appendStringInfo(buf, "ROW(");
sep = "";
foreach(arg, rowexpr->args)
{
Node *e = (Node *) lfirst(arg);
appendStringInfo(buf, sep);
get_rule_expr(e, context, true);
sep = ", ";
}
appendStringInfo(buf, ")");
if (rowexpr->row_format == COERCE_EXPLICIT_CAST)
appendStringInfo(buf, "::%s",
format_type_with_typemod(rowexpr->row_typeid, -1));
}
break;
case T_CoalesceExpr:
{
CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;