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First cut at implementing IN (and NOT IN) via hashtables. There is

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more to be done yet, but this is a good start.
This commit is contained in:
Tom Lane
2003-01-12 04:03:34 +00:00
parent 3e54e26bcf
commit 19b886332a
7 changed files with 712 additions and 132 deletions
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33
src/include/nodes/execnodes.h
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@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: execnodes.h,v 1.90 2003/01/10 23:54:24 tgl Exp $
* $Id: execnodes.h,v 1.91 2003/01/12 04:03:34 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -170,27 +170,34 @@ typedef struct ReturnSetInfo
/* ----------------
* ProjectionInfo node information
*
* This is all the information needed to perform projections
* on a tuple. Nodes which need to do projections create one
* of these. In theory, when a node wants to perform a projection
* This is all the information needed to perform projections ---
* that is, form new tuples by evaluation of targetlist expressions.
* Nodes which need to do projections create one of these.
* In theory, when a node wants to perform a projection
* it should just update this information as necessary and then
* call ExecProject(). -cim 6/3/91
*
* ExecProject() evaluates the tlist, forms a tuple, and stores it
* in the given slot. As a side-effect, the actual datum values and
* null indicators are placed in the work arrays tupValues/tupNulls.
*
* targetlist target list for projection
* len length of target list
* tupValue array of pointers to projection results
* exprContext expression context for ExecTargetList
* exprContext expression context in which to evaluate targetlist
* slot slot to place projection result in
* tupValues array of computed values
* tupNull array of null indicators
* itemIsDone workspace for ExecProject
* ----------------
*/
typedef struct ProjectionInfo
{
NodeTag type;
List *pi_targetlist;
int pi_len;
Datum *pi_tupValue;
ExprContext *pi_exprContext;
TupleTableSlot *pi_slot;
Datum *pi_tupValues;
char *pi_tupNulls;
ExprDoneCond *pi_itemIsDone;
} ProjectionInfo;
/* ----------------
@ -495,8 +502,16 @@ typedef struct SubPlanState
bool needShutdown; /* TRUE = need to shutdown subplan */
HeapTuple curTuple; /* copy of most recent tuple from subplan */
/* these are used when hashing the subselect's output: */
ProjectionInfo *projLeft; /* for projecting lefthand exprs */
ProjectionInfo *projRight; /* for projecting subselect output */
TupleHashTable hashtable; /* hash table for no-nulls subselect rows */
TupleHashTable hashnulls; /* hash table for rows with null(s) */
bool havehashrows; /* TRUE if hashtable is not empty */
bool havenullrows; /* TRUE if hashnulls is not empty */
MemoryContext tablecxt; /* memory context containing tables */
ExprContext *innerecontext; /* working context for comparisons */
AttrNumber *keyColIdx; /* control data for hash tables */
FmgrInfo *eqfunctions; /* comparison functions for hash tables */
} SubPlanState;
/* ----------------