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Standard pgindent run for 8.1.

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This commit is contained in:
Bruce Momjian
2005-10-15 02:49:52 +00:00
parent 790c01d280
commit 1dc3498251
770 changed files with 34334 additions and 32507 deletions
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243
src/backend/executor/nodeSubplan.c
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@@ -7,7 +7,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/nodeSubplan.c,v 1.69 2005/05/06 17:24:54 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/nodeSubplan.c,v 1.70 2005/10/15 02:49:17 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -86,15 +86,15 @@ ExecHashSubPlan(SubPlanState *node,
elog(ERROR, "hashed subplan with direct correlation not supported");
/*
* If first time through or we need to rescan the subplan, build the
* hash table.
* If first time through or we need to rescan the subplan, build the hash
* table.
*/
if (node->hashtable == NULL || planstate->chgParam != NULL)
buildSubPlanHash(node);
/*
* The result for an empty subplan is always FALSE; no need to
* evaluate lefthand side.
* The result for an empty subplan is always FALSE; no need to evaluate
* lefthand side.
*/
*isNull = false;
if (!node->havehashrows && !node->havenullrows)
@@ -108,34 +108,32 @@ ExecHashSubPlan(SubPlanState *node,
slot = ExecProject(node->projLeft, NULL);
/*
* Note: because we are typically called in a per-tuple context, we
* have to explicitly clear the projected tuple before returning.
* Otherwise, we'll have a double-free situation: the per-tuple
* context will probably be reset before we're called again, and then
* the tuple slot will think it still needs to free the tuple.
* Note: because we are typically called in a per-tuple context, we have
* to explicitly clear the projected tuple before returning. Otherwise,
* we'll have a double-free situation: the per-tuple context will probably
* be reset before we're called again, and then the tuple slot will think
* it still needs to free the tuple.
*/
/*
* Since the hashtable routines will use innerecontext's per-tuple
* memory as working memory, be sure to reset it for each tuple.
* Since the hashtable routines will use innerecontext's per-tuple memory
* as working memory, be sure to reset it for each tuple.
*/
ResetExprContext(innerecontext);
/*
* If the LHS is all non-null, probe for an exact match in the main
* hash table. If we find one, the result is TRUE. Otherwise, scan
* the partly-null table to see if there are any rows that aren't
* provably unequal to the LHS; if so, the result is UNKNOWN. (We
* skip that part if we don't care about UNKNOWN.) Otherwise, the
* result is FALSE.
* If the LHS is all non-null, probe for an exact match in the main hash
* table. If we find one, the result is TRUE. Otherwise, scan the
* partly-null table to see if there are any rows that aren't provably
* unequal to the LHS; if so, the result is UNKNOWN. (We skip that part
* if we don't care about UNKNOWN.) Otherwise, the result is FALSE.
*
* Note: the reason we can avoid a full scan of the main hash table is
* that the combining operators are assumed never to yield NULL when
* both inputs are non-null. If they were to do so, we might need to
* produce UNKNOWN instead of FALSE because of an UNKNOWN result in
* comparing the LHS to some main-table entry --- which is a
* comparison we will not even make, unless there's a chance match of
* hash keys.
* Note: the reason we can avoid a full scan of the main hash table is that
* the combining operators are assumed never to yield NULL when both
* inputs are non-null. If they were to do so, we might need to produce
* UNKNOWN instead of FALSE because of an UNKNOWN result in comparing the
* LHS to some main-table entry --- which is a comparison we will not even
* make, unless there's a chance match of hash keys.
*/
if (slotNoNulls(slot))
{
@@ -157,14 +155,14 @@ ExecHashSubPlan(SubPlanState *node,
}
/*
* When the LHS is partly or wholly NULL, we can never return TRUE. If
* we don't care about UNKNOWN, just return FALSE. Otherwise, if the
* LHS is wholly NULL, immediately return UNKNOWN. (Since the
* combining operators are strict, the result could only be FALSE if
* the sub-select were empty, but we already handled that case.)
* Otherwise, we must scan both the main and partly-null tables to see
* if there are any rows that aren't provably unequal to the LHS; if
* so, the result is UNKNOWN. Otherwise, the result is FALSE.
* When the LHS is partly or wholly NULL, we can never return TRUE. If we
* don't care about UNKNOWN, just return FALSE. Otherwise, if the LHS is
* wholly NULL, immediately return UNKNOWN. (Since the combining
* operators are strict, the result could only be FALSE if the sub-select
* were empty, but we already handled that case.) Otherwise, we must scan
* both the main and partly-null tables to see if there are any rows that
* aren't provably unequal to the LHS; if so, the result is UNKNOWN.
* Otherwise, the result is FALSE.
*/
if (node->hashnulls == NULL)
{
@@ -217,9 +215,9 @@ ExecScanSubPlan(SubPlanState *node,
ArrayBuildState *astate = NULL;
/*
* We are probably in a short-lived expression-evaluation context.
* Switch to the child plan's per-query context for manipulating its
* chgParam, calling ExecProcNode on it, etc.
* We are probably in a short-lived expression-evaluation context. Switch
* to the child plan's per-query context for manipulating its chgParam,
* calling ExecProcNode on it, etc.
*/
oldcontext = MemoryContextSwitchTo(node->sub_estate->es_query_cxt);
@@ -245,24 +243,23 @@ ExecScanSubPlan(SubPlanState *node,
ExecReScan(planstate, NULL);
/*
* For all sublink types except EXPR_SUBLINK and ARRAY_SUBLINK, the
* result is boolean as are the results of the combining operators. We
* combine results within a tuple (if there are multiple columns)
* using OR semantics if "useOr" is true, AND semantics if not. We
* then combine results across tuples (if the subplan produces more
* than one) using OR semantics for ANY_SUBLINK or AND semantics for
* ALL_SUBLINK. (MULTIEXPR_SUBLINK doesn't allow multiple tuples from
* the subplan.) NULL results from the combining operators are handled
* according to the usual SQL semantics for OR and AND. The result
* for no input tuples is FALSE for ANY_SUBLINK, TRUE for ALL_SUBLINK,
* NULL for MULTIEXPR_SUBLINK.
* For all sublink types except EXPR_SUBLINK and ARRAY_SUBLINK, the result
* is boolean as are the results of the combining operators. We combine
* results within a tuple (if there are multiple columns) using OR
* semantics if "useOr" is true, AND semantics if not. We then combine
* results across tuples (if the subplan produces more than one) using OR
* semantics for ANY_SUBLINK or AND semantics for ALL_SUBLINK.
* (MULTIEXPR_SUBLINK doesn't allow multiple tuples from the subplan.)
* NULL results from the combining operators are handled according to the
* usual SQL semantics for OR and AND. The result for no input tuples is
* FALSE for ANY_SUBLINK, TRUE for ALL_SUBLINK, NULL for
* MULTIEXPR_SUBLINK.
*
* For EXPR_SUBLINK we require the subplan to produce no more than one
* tuple, else an error is raised. For ARRAY_SUBLINK we allow the
* subplan to produce more than one tuple. In either case, if zero
* tuples are produced, we return NULL. Assuming we get a tuple, we
* just use its first column (there can be only one non-junk column in
* this case).
* For EXPR_SUBLINK we require the subplan to produce no more than one tuple,
* else an error is raised. For ARRAY_SUBLINK we allow the subplan to
* produce more than one tuple. In either case, if zero tuples are
* produced, we return NULL. Assuming we get a tuple, we just use its
* first column (there can be only one non-junk column in this case).
*/
result = BoolGetDatum(subLinkType == ALL_SUBLINK);
*isNull = false;
@@ -294,12 +291,12 @@ ExecScanSubPlan(SubPlanState *node,
found = true;
/*
* We need to copy the subplan's tuple in case the result is
* of pass-by-ref type --- our return value will point into
* this copied tuple! Can't use the subplan's instance of the
* tuple since it won't still be valid after next
* ExecProcNode() call. node->curTuple keeps track of the
* copied tuple for eventual freeing.
* We need to copy the subplan's tuple in case the result is of
* pass-by-ref type --- our return value will point into this
* copied tuple! Can't use the subplan's instance of the tuple
* since it won't still be valid after next ExecProcNode() call.
* node->curTuple keeps track of the copied tuple for eventual
* freeing.
*/
MemoryContextSwitchTo(econtext->ecxt_per_query_memory);
if (node->curTuple)
@@ -350,8 +347,7 @@ ExecScanSubPlan(SubPlanState *node,
bool expnull;
/*
* Load up the Param representing this column of the
* sub-select.
* Load up the Param representing this column of the sub-select.
*/
prmdata = &(econtext->ecxt_param_exec_vals[paramid]);
Assert(prmdata->execPlan == NULL);
@@ -436,8 +432,8 @@ ExecScanSubPlan(SubPlanState *node,
{
/*
* deal with empty subplan result. result/isNull were previously
* initialized correctly for all sublink types except EXPR, ARRAY,
* and MULTIEXPR; for those, return NULL.
* initialized correctly for all sublink types except EXPR, ARRAY, and
* MULTIEXPR; for those, return NULL.
*/
if (subLinkType == EXPR_SUBLINK ||
subLinkType == ARRAY_SUBLINK ||
@@ -478,19 +474,19 @@ buildSubPlanHash(SubPlanState *node)
Assert(!subplan->useOr);
/*
* If we already had any hash tables, destroy 'em; then create empty
* hash table(s).
* If we already had any hash tables, destroy 'em; then create empty hash
* table(s).
*
* If we need to distinguish accurately between FALSE and UNKNOWN (i.e.,
* NULL) results of the IN operation, then we have to store subplan
* output rows that are partly or wholly NULL. We store such rows in
* a separate hash table that we expect will be much smaller than the
* main table. (We can use hashing to eliminate partly-null rows that
* are not distinct. We keep them separate to minimize the cost of
* the inevitable full-table searches; see findPartialMatch.)
* NULL) results of the IN operation, then we have to store subplan output
* rows that are partly or wholly NULL. We store such rows in a separate
* hash table that we expect will be much smaller than the main table.
* (We can use hashing to eliminate partly-null rows that are not
* distinct. We keep them separate to minimize the cost of the inevitable
* full-table searches; see findPartialMatch.)
*
* If it's not necessary to distinguish FALSE and UNKNOWN, then we don't
* need to store subplan output rows that contain NULL.
* If it's not necessary to distinguish FALSE and UNKNOWN, then we don't need
* to store subplan output rows that contain NULL.
*/
MemoryContextReset(node->tablecxt);
node->hashtable = NULL;
@@ -532,9 +528,8 @@ buildSubPlanHash(SubPlanState *node)
}
/*
* We are probably in a short-lived expression-evaluation context.
* Switch to the child plan's per-query context for calling
* ExecProcNode.
* We are probably in a short-lived expression-evaluation context. Switch
* to the child plan's per-query context for calling ExecProcNode.
*/
oldcontext = MemoryContextSwitchTo(node->sub_estate->es_query_cxt);
@@ -544,9 +539,8 @@ buildSubPlanHash(SubPlanState *node)
ExecReScan(planstate, NULL);
/*
* Scan the subplan and load the hash table(s). Note that when there
* are duplicate rows coming out of the sub-select, only one copy is
* stored.
* Scan the subplan and load the hash table(s). Note that when there are
* duplicate rows coming out of the sub-select, only one copy is stored.
*/
for (slot = ExecProcNode(planstate);
!TupIsNull(slot);
@@ -557,8 +551,8 @@ buildSubPlanHash(SubPlanState *node)
bool isnew;
/*
* Load up the Params representing the raw sub-select outputs,
* then form the projection tuple to store in the hashtable.
* Load up the Params representing the raw sub-select outputs, then
* form the projection tuple to store in the hashtable.
*/
foreach(plst, subplan->paramIds)
{
@@ -588,18 +582,18 @@ buildSubPlanHash(SubPlanState *node)
}
/*
* Reset innerecontext after each inner tuple to free any memory
* used in hash computation or comparison routines.
* Reset innerecontext after each inner tuple to free any memory used
* in hash computation or comparison routines.
*/
ResetExprContext(innerecontext);
}
/*
* Since the projected tuples are in the sub-query's context and not
* the main context, we'd better clear the tuple slot before there's
* any chance of a reset of the sub-query's context. Else we will
* have the potential for a double free attempt. (XXX possibly
* no longer needed, but can't hurt.)
* Since the projected tuples are in the sub-query's context and not the
* main context, we'd better clear the tuple slot before there's any
* chance of a reset of the sub-query's context. Else we will have the
* potential for a double free attempt. (XXX possibly no longer needed,
* but can't hurt.)
*/
ExecClearTuple(node->projRight->pi_slot);
@@ -710,10 +704,10 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
/*
* create an EState for the subplan
*
* The subquery needs its own EState because it has its own rangetable.
* It shares our Param ID space, however. XXX if rangetable access
* were done differently, the subquery could share our EState, which
* would eliminate some thrashing about in this module...
* The subquery needs its own EState because it has its own rangetable. It
* shares our Param ID space, however. XXX if rangetable access were done
* differently, the subquery could share our EState, which would eliminate
* some thrashing about in this module...
*/
sp_estate = CreateExecutorState();
node->sub_estate = sp_estate;
@@ -739,13 +733,12 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
MemoryContextSwitchTo(oldcontext);
/*
* If this plan is un-correlated or undirect correlated one and want
* to set params for parent plan then mark parameters as needing
* evaluation.
* If this plan is un-correlated or undirect correlated one and want to
* set params for parent plan then mark parameters as needing evaluation.
*
* Note that in the case of un-correlated subqueries we don't care about
* setting parent->chgParam here: indices take care about it, for
* others - it doesn't matter...
* setting parent->chgParam here: indices take care about it, for others -
* it doesn't matter...
*/
if (subplan->setParam != NIL)
{
@@ -761,8 +754,8 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
}
/*
* If we are going to hash the subquery output, initialize relevant
* stuff. (We don't create the hashtable until needed, though.)
* If we are going to hash the subquery output, initialize relevant stuff.
* (We don't create the hashtable until needed, though.)
*/
if (subplan->useHashTable)
{
@@ -794,18 +787,17 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
/*
* We use ExecProject to evaluate the lefthand and righthand
* expression lists and form tuples. (You might think that we
* could use the sub-select's output tuples directly, but that is
* not the case if we had to insert any run-time coercions of the
* sub-select's output datatypes; anyway this avoids storing any
* resjunk columns that might be in the sub-select's output.) Run
* through the combining expressions to build tlists for the
* lefthand and righthand sides. We need both the ExprState list
* (for ExecProject) and the underlying parse Exprs (for
* ExecTypeFromTL).
* expression lists and form tuples. (You might think that we could
* use the sub-select's output tuples directly, but that is not the
* case if we had to insert any run-time coercions of the sub-select's
* output datatypes; anyway this avoids storing any resjunk columns
* that might be in the sub-select's output.) Run through the
* combining expressions to build tlists for the lefthand and
* righthand sides. We need both the ExprState list (for ExecProject)
* and the underlying parse Exprs (for ExecTypeFromTL).
*
* We also extract the combining operators themselves to initialize
* the equality and hashing functions for the hash tables.
* We also extract the combining operators themselves to initialize the
* equality and hashing functions for the hash tables.
*/
lefttlist = righttlist = NIL;
leftptlist = rightptlist = NIL;
@@ -869,21 +861,21 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
}
/*
* Create a tupletable to hold these tuples. (Note: we never
* bother to free the tupletable explicitly; that's okay because
* it will never store raw disk tuples that might have associated
* buffer pins. The only resource involved is memory, which will
* be cleaned up by freeing the query context.)
* Create a tupletable to hold these tuples. (Note: we never bother
* to free the tupletable explicitly; that's okay because it will
* never store raw disk tuples that might have associated buffer pins.
* The only resource involved is memory, which will be cleaned up by
* freeing the query context.)
*/
tupTable = ExecCreateTupleTable(2);
/*
* Construct tupdescs, slots and projection nodes for left and
* right sides. The lefthand expressions will be evaluated in the
* parent plan node's exprcontext, which we don't have access to
* here. Fortunately we can just pass NULL for now and fill it in
* later (hack alert!). The righthand expressions will be
* evaluated in our own innerecontext.
* Construct tupdescs, slots and projection nodes for left and right
* sides. The lefthand expressions will be evaluated in the parent
* plan node's exprcontext, which we don't have access to here.
* Fortunately we can just pass NULL for now and fill it in later
* (hack alert!). The righthand expressions will be evaluated in our
* own innerecontext.
*/
tupDesc = ExecTypeFromTL(leftptlist, false);
slot = ExecAllocTableSlot(tupTable);
@@ -983,11 +975,10 @@ ExecSetParamPlan(SubPlanState *node, ExprContext *econtext)
found = true;
/*
* We need to copy the subplan's tuple into our own context, in
* case any of the params are pass-by-ref type --- the pointers
* stored in the param structs will point at this copied tuple!
* node->curTuple keeps track of the copied tuple for eventual
* freeing.
* We need to copy the subplan's tuple into our own context, in case
* any of the params are pass-by-ref type --- the pointers stored in
* the param structs will point at this copied tuple! node->curTuple
* keeps track of the copied tuple for eventual freeing.
*/
MemoryContextSwitchTo(econtext->ecxt_per_query_memory);
if (node->curTuple)