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This commit is contained in:
Bruce Momjian 1999-02-24 10:20:07 +00:00
parent 02fa3e4394
commit f3f7c2acde
1 changed files with 89 additions and 78 deletions
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167
src/backend/executor/nodeMergejoin.c
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@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/executor/nodeMergejoin.c,v 1.23 1999/02/23 07:35:09 thomas Exp $
* $Header: /cvsroot/pgsql/src/backend/executor/nodeMergejoin.c,v 1.24 1999/02/24 10:20:07 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -288,7 +288,7 @@ MergeCompare(List *eqQual, List *compareQual, ExprContext *econtext)
*/
#ifdef EXEC_MERGEJOINDEBUG
void
ExecMergeTupleDumpInner(ExprContext *econtext);
ExecMergeTupleDumpInner(ExprContext *econtext);
void
ExecMergeTupleDumpInner(ExprContext *econtext)
@ -305,7 +305,7 @@ ExecMergeTupleDumpInner(ExprContext *econtext)
}
void
ExecMergeTupleDumpOuter(ExprContext *econtext);
ExecMergeTupleDumpOuter(ExprContext *econtext);
void
ExecMergeTupleDumpOuter(ExprContext *econtext)
@ -321,8 +321,7 @@ ExecMergeTupleDumpOuter(ExprContext *econtext)
outerSlot->ttc_tupleDescriptor);
}
void
ExecMergeTupleDumpMarked(ExprContext *econtext,
void ExecMergeTupleDumpMarked(ExprContext *econtext,
MergeJoinState *mergestate);
void
@ -342,7 +341,7 @@ ExecMergeTupleDumpMarked(ExprContext *econtext,
}
void
ExecMergeTupleDump(ExprContext *econtext, MergeJoinState *mergestate);
ExecMergeTupleDump(ExprContext *econtext, MergeJoinState *mergestate);
void
ExecMergeTupleDump(ExprContext *econtext, MergeJoinState *mergestate)
@ -355,6 +354,7 @@ ExecMergeTupleDump(ExprContext *econtext, MergeJoinState *mergestate)
printf("******** \n");
}
#endif
/* ----------------------------------------------------------------
@ -427,11 +427,14 @@ ExecMergeJoin(MergeJoin *node)
ExprContext *econtext;
#ifdef ENABLE_OUTER_JOINS
/* These should be set from the expression context!
* - thomas 1999-02-20
/*
* These should be set from the expression context! - thomas
* 1999-02-20
*/
static bool isLeftJoin = true;
static bool isRightJoin = false;
#endif
/* ----------------
@ -486,19 +489,19 @@ ExecMergeJoin(MergeJoin *node)
switch (mergestate->mj_JoinState)
{
/*********************************
/*
* EXEC_MJ_INITIALIZE means that this is the first time
* ExecMergeJoin() has been called and so we have to initialize
* the inner, outer and marked tuples as well as various stuff
* in the expression context.
*********************************/
* ExecMergeJoin() has been called and so we have to
* initialize the inner, outer and marked tuples as well
* as various stuff in the expression context.
*/
case EXEC_MJ_INITIALIZE:
MJ_printf("ExecMergeJoin: EXEC_MJ_INITIALIZE\n");
/* ----------------
* Note: at this point, if either of our inner or outer
* tuples are nil, then the join ends immediately because
* we know one of the subplans is empty.
* ----------------
/*
* Note: at this point, if either of our inner or outer
* tuples are nil, then the join ends immediately because
* we know one of the subplans is empty.
*/
innerTupleSlot = ExecProcNode(innerPlan, (Plan *) node);
if (TupIsNull(innerTupleSlot))
@ -531,11 +534,12 @@ ExecMergeJoin(MergeJoin *node)
mergestate->mj_JoinState = EXEC_MJ_SKIPINNER;
break;
/*********************************
* EXEC_MJ_JOINMARK means we have just found a new outer tuple
* and a possible matching inner tuple. This is the case after
* the INITIALIZE, SKIPOUTER or SKIPINNER states.
*********************************/
/*
* EXEC_MJ_JOINMARK means we have just found a new outer
* tuple and a possible matching inner tuple. This is the
* case after the INITIALIZE, SKIPOUTER or SKIPINNER
* states.
*/
case EXEC_MJ_JOINMARK:
MJ_printf("ExecMergeJoin: EXEC_MJ_JOINMARK\n");
ExecMarkPos(innerPlan);
@ -545,7 +549,7 @@ ExecMergeJoin(MergeJoin *node)
mergestate->mj_JoinState = EXEC_MJ_JOINTEST;
break;
/*********************************
/*
* EXEC_MJ_JOINTEST means we have two tuples which might
* satisfy the merge clause, so we test them.
*
@ -553,7 +557,7 @@ ExecMergeJoin(MergeJoin *node)
* next inner tuple (EXEC_MJ_JOINTUPLES).
*
* If they do not satisfy then advance to next outer tuple.
*********************************/
*/
case EXEC_MJ_JOINTEST:
MJ_printf("ExecMergeJoin: EXEC_MJ_JOINTEST\n");
@ -566,11 +570,11 @@ ExecMergeJoin(MergeJoin *node)
mergestate->mj_JoinState = EXEC_MJ_NEXTOUTER;
break;
/*********************************
/*
* EXEC_MJ_JOINTUPLES means we have two tuples which
* satisified the merge clause so we join them and then
* proceed to get the next inner tuple (EXEC_NEXT_INNER).
*********************************/
*/
case EXEC_MJ_JOINTUPLES:
MJ_printf("ExecMergeJoin: EXEC_MJ_JOINTUPLES\n");
mergestate->mj_JoinState = EXEC_MJ_NEXTINNER;
@ -599,11 +603,11 @@ ExecMergeJoin(MergeJoin *node)
}
break;
/*********************************
* EXEC_MJ_NEXTINNER means advance the inner scan to
* the next tuple. If the tuple is not nil, we then
* proceed to test it against the join qualification.
*********************************/
/*
* EXEC_MJ_NEXTINNER means advance the inner scan to the
* next tuple. If the tuple is not nil, we then proceed to
* test it against the join qualification.
*/
case EXEC_MJ_NEXTINNER:
MJ_printf("ExecMergeJoin: EXEC_MJ_NEXTINNER\n");
@ -621,21 +625,22 @@ ExecMergeJoin(MergeJoin *node)
mergestate->mj_JoinState = EXEC_MJ_JOINTEST;
break;
/*********************************
/*-------------------------------------------
* EXEC_MJ_NEXTOUTER means
*
* outer inner
* outer tuple - 5 5 - marked tuple
* 5 5
* 6 6 - inner tuple
* 7 7
* outer inner
* outer tuple - 5 5 - marked tuple
* 5 5
* 6 6 - inner tuple
* 7 7
*
* we know we just bumped into the
* we know we just bumped into the
* first inner tuple > current outer tuple
* so get a new outer tuple and then
* proceed to test it against the marked tuple
* (EXEC_MJ_TESTOUTER)
*********************************/
*------------------------------------------------
*/
case EXEC_MJ_NEXTOUTER:
MJ_printf("ExecMergeJoin: EXEC_MJ_NEXTOUTER\n");
@ -657,7 +662,7 @@ ExecMergeJoin(MergeJoin *node)
mergestate->mj_JoinState = EXEC_MJ_TESTOUTER;
break;
/*********************************
/*--------------------------------------------------------
* EXEC_MJ_TESTOUTER If the new outer tuple and the marked
* tuple satisfy the merge clause then we know we have
* duplicates in the outer scan so we have to restore the
@ -687,9 +692,10 @@ ExecMergeJoin(MergeJoin *node)
* 7 12
*
*
* new outer tuple > marked tuple
* new outer tuple > marked tuple
*
*********************************/
*---------------------------------------------------------
*/
case EXEC_MJ_TESTOUTER:
MJ_printf("ExecMergeJoin: EXEC_MJ_TESTOUTER\n");
@ -731,11 +737,11 @@ ExecMergeJoin(MergeJoin *node)
* tuple didn't match the marked outer tuple then
* we may have the case:
*
* outer inner
* 4 4 - marked tuple
* new outer - 5 4
* 6 nil - inner tuple
* 7
* outer inner
* 4 4 - marked tuple
* new outer - 5 4
* 6 nil - inner tuple
* 7
*
* which means that all subsequent outer tuples will be
* larger than our inner tuples.
@ -760,22 +766,23 @@ ExecMergeJoin(MergeJoin *node)
}
break;
/*********************************
/*----------------------------------------------------------
* EXEC_MJ_SKIPOUTER means skip over tuples in the outer plan
* until we find an outer tuple > current inner tuple.
*
* For example:
*
* outer inner
* 5 5
* 5 5
* outer tuple - 6 8 - inner tuple
* 7 12
* 8 14
* outer inner
* 5 5
* 5 5
* outer tuple - 6 8 - inner tuple
* 7 12
* 8 14
*
* we have to advance the outer scan
* until we find the outer 8.
*********************************/
*----------------------------------------------------------
*/
case EXEC_MJ_SKIPOUTER:
MJ_printf("ExecMergeJoin: EXEC_MJ_SKIPOUTER\n");
/* ----------------
@ -867,23 +874,24 @@ ExecMergeJoin(MergeJoin *node)
mergestate->mj_JoinState = EXEC_MJ_JOINMARK;
break;
/*********************************
/*-----------------------------------------------------------
* EXEC_MJ_SKIPINNER means skip over tuples in the inner plan
* until we find an inner tuple > current outer tuple.
*
* For example:
*
* outer inner
* 5 5
* 5 5
* outer tuple - 12 8 - inner tuple
* 14 10
* 17 12
* outer inner
* 5 5
* 5 5
* outer tuple - 12 8 - inner tuple
* 14 10
* 17 12
*
* we have to advance the inner scan
* until we find the inner 12.
*
*********************************/
*-------------------------------------------------------
*/
case EXEC_MJ_SKIPINNER:
MJ_printf("ExecMergeJoin: EXEC_MJ_SKIPINNER\n");
/* ----------------
@ -997,11 +1005,13 @@ ExecMergeJoin(MergeJoin *node)
break;
#ifdef ENABLE_OUTER_JOINS
/*********************************
* EXEC_MJ_FILLINNER means we have an unmatched inner tuple
* which must be null-expanded into the projection tuple.
* get the next inner tuple and reset markers (EXEC_MJ_JOINMARK).
*********************************/
/*
* EXEC_MJ_FILLINNER means we have an unmatched inner
* tuple which must be null-expanded into the projection
* tuple. get the next inner tuple and reset markers
* (EXEC_MJ_JOINMARK).
*/
case EXEC_MJ_FILLINNER:
MJ_printf("ExecMergeJoin: EXEC_MJ_FILLINNER\n");
mergestate->mj_JoinState = EXEC_MJ_JOINMARK;
@ -1046,11 +1056,12 @@ ExecMergeJoin(MergeJoin *node)
*/
break;
/*********************************
* EXEC_MJ_FILLOUTER means we have an unmatched outer tuple
* which must be null-expanded into the projection tuple.
* get the next outer tuple and reset markers (EXEC_MJ_JOINMARK).
*********************************/
/*
* EXEC_MJ_FILLOUTER means we have an unmatched outer
* tuple which must be null-expanded into the projection
* tuple. get the next outer tuple and reset markers
* (EXEC_MJ_JOINMARK).
*/
case EXEC_MJ_FILLOUTER:
MJ_printf("ExecMergeJoin: EXEC_MJ_FILLOUTER\n");
mergestate->mj_JoinState = EXEC_MJ_JOINMARK;
@ -1095,10 +1106,10 @@ ExecMergeJoin(MergeJoin *node)
break;
#endif
/*********************************
* if we get here it means our code is fouled up
* and so we just end the join prematurely.
*********************************/
/*
* if we get here it means our code is fouled up and so we
* just end the join prematurely.
*/
default:
elog(NOTICE, "ExecMergeJoin: invalid join state. aborting");
return NULL;