From f3f7c2acdeaa19b2d85d0f1522ebdfab1e466210 Mon Sep 17 00:00:00 2001 From: Bruce Momjian Date: Wed, 24 Feb 1999 10:20:07 +0000 Subject: [PATCH] update comments --- src/backend/executor/nodeMergejoin.c | 167 ++++++++++++++------------- 1 file changed, 89 insertions(+), 78 deletions(-) diff --git a/src/backend/executor/nodeMergejoin.c b/src/backend/executor/nodeMergejoin.c index db22520bc6..9fc0aed112 100644 --- a/src/backend/executor/nodeMergejoin.c +++ b/src/backend/executor/nodeMergejoin.c @@ -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;