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pgindent run.

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This commit is contained in:
Bruce Momjian
2003-08-04 00:43:34 +00:00
parent 63354a0228
commit 089003fb46
554 changed files with 24888 additions and 21245 deletions
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41
src/backend/executor/nodeLimit.c
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@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/executor/nodeLimit.c,v 1.15 2003/07/21 17:05:09 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/executor/nodeLimit.c,v 1.16 2003/08/04 00:43:18 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -55,17 +55,21 @@ ExecLimit(LimitState *node)
switch (node->lstate)
{
case LIMIT_INITIAL:
/*
* If backwards scan, just return NULL without changing state.
*/
if (!ScanDirectionIsForward(direction))
return NULL;
/*
* First call for this scan, so compute limit/offset. (We can't do
* this any earlier, because parameters from upper nodes may not
* be set until now.) This also sets position = 0.
* First call for this scan, so compute limit/offset. (We
* can't do this any earlier, because parameters from upper
* nodes may not be set until now.) This also sets position =
* 0.
*/
recompute_limits(node);
/*
* Check for empty window; if so, treat like empty subplan.
*/
@ -74,6 +78,7 @@ ExecLimit(LimitState *node)
node->lstate = LIMIT_EMPTY;
return NULL;
}
/*
* Fetch rows from subplan until we reach position > offset.
*/
@ -83,8 +88,8 @@ ExecLimit(LimitState *node)
if (TupIsNull(slot))
{
/*
* The subplan returns too few tuples for us to produce
* any output at all.
* The subplan returns too few tuples for us to
* produce any output at all.
*/
node->lstate = LIMIT_EMPTY;
return NULL;
@ -93,6 +98,7 @@ ExecLimit(LimitState *node)
if (++node->position > node->offset)
break;
}
/*
* Okay, we have the first tuple of the window.
*/
@ -100,9 +106,10 @@ ExecLimit(LimitState *node)
break;
case LIMIT_EMPTY:
/*
* The subplan is known to return no tuples (or not more than
* OFFSET tuples, in general). So we return no tuples.
* OFFSET tuples, in general). So we return no tuples.
*/
return NULL;
@ -113,7 +120,8 @@ ExecLimit(LimitState *node)
* Forwards scan, so check for stepping off end of window.
* If we are at the end of the window, return NULL without
* advancing the subplan or the position variable; but
* change the state machine state to record having done so.
* change the state machine state to record having done
* so.
*/
if (!node->noCount &&
node->position >= node->offset + node->count)
@ -121,6 +129,7 @@ ExecLimit(LimitState *node)
node->lstate = LIMIT_WINDOWEND;
return NULL;
}
/*
* Get next tuple from subplan, if any.
*/
@ -136,14 +145,16 @@ ExecLimit(LimitState *node)
else
{
/*
* Backwards scan, so check for stepping off start of window.
* As above, change only state-machine status if so.
* Backwards scan, so check for stepping off start of
* window. As above, change only state-machine status if
* so.
*/
if (node->position <= node->offset + 1)
{
node->lstate = LIMIT_WINDOWSTART;
return NULL;
}
/*
* Get previous tuple from subplan; there should be one!
*/
@ -158,9 +169,11 @@ ExecLimit(LimitState *node)
case LIMIT_SUBPLANEOF:
if (ScanDirectionIsForward(direction))
return NULL;
/*
* Backing up from subplan EOF, so re-fetch previous tuple;
* there should be one! Note previous tuple must be in window.
* there should be one! Note previous tuple must be in
* window.
*/
slot = ExecProcNode(outerPlan);
if (TupIsNull(slot))
@ -173,9 +186,10 @@ ExecLimit(LimitState *node)
case LIMIT_WINDOWEND:
if (ScanDirectionIsForward(direction))
return NULL;
/*
* Backing up from window end: simply re-return the last
* tuple fetched from the subplan.
* Backing up from window end: simply re-return the last tuple
* fetched from the subplan.
*/
slot = node->subSlot;
node->lstate = LIMIT_INWINDOW;
@ -185,6 +199,7 @@ ExecLimit(LimitState *node)
case LIMIT_WINDOWSTART:
if (!ScanDirectionIsForward(direction))
return NULL;
/*
* Advancing after having backed off window start: simply
* re-return the last tuple fetched from the subplan.