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Diffstat (limited to 'src/backend/access/nbtree/nbtsearch.c')
-rw-r--r--src/backend/access/nbtree/nbtsearch.c75
1 files changed, 39 insertions, 36 deletions
diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c
index f36da9743f8..cad117e5e61 100644
--- a/src/backend/access/nbtree/nbtsearch.c
+++ b/src/backend/access/nbtree/nbtsearch.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.58 2000/03/17 02:36:04 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.59 2000/04/12 17:14:49 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -299,9 +299,7 @@ _bt_skeycmp(Relation rel,
compare = -1; /* not-NULL key "<" NULL datum */
}
else
- {
compare = (int32) FMGR_PTR2(&entry->sk_func, keyDatum, attrDatum);
- }
if (compare != 0)
break; /* done when we find unequal attributes */
@@ -368,26 +366,26 @@ _bt_binsrch(Relation rel,
/*
* If there are no keys on the page, return the first available slot.
- * Note this covers two cases: the page is really empty (no keys),
- * or it contains only a high key. The latter case is possible after
+ * Note this covers two cases: the page is really empty (no keys), or
+ * it contains only a high key. The latter case is possible after
* vacuuming.
*/
if (high < low)
return low;
/*
- * Binary search to find the first key on the page >= scan key.
- * Loop invariant: all slots before 'low' are < scan key, all slots
- * at or after 'high' are >= scan key. Also, haveEq is true if the
- * tuple at 'high' is == scan key.
- * We can fall out when high == low.
+ * Binary search to find the first key on the page >= scan key. Loop
+ * invariant: all slots before 'low' are < scan key, all slots at or
+ * after 'high' are >= scan key. Also, haveEq is true if the tuple at
+ * 'high' is == scan key. We can fall out when high == low.
*/
high++; /* establish the loop invariant for high */
haveEq = false;
while (high > low)
{
- OffsetNumber mid = low + ((high - low) / 2);
+ OffsetNumber mid = low + ((high - low) / 2);
+
/* We have low <= mid < high, so mid points at a real slot */
result = _bt_compare(rel, itupdesc, page, keysz, scankey, mid);
@@ -403,7 +401,7 @@ _bt_binsrch(Relation rel,
/*--------------------
* At this point we have high == low, but be careful: they could point
- * past the last slot on the page. We also know that haveEq is true
+ * past the last slot on the page. We also know that haveEq is true
* if and only if there is an equal key (in which case high&low point
* at the first equal key).
*
@@ -443,18 +441,20 @@ _bt_binsrch(Relation rel,
if (haveEq)
{
+
/*
* There is an equal key. We return either the first equal key
* (which we just found), or the last lesser key.
*
- * We need not check srchtype != BT_DESCENT here, since if that
- * is true then natts == keysz by assumption.
+ * We need not check srchtype != BT_DESCENT here, since if that is
+ * true then natts == keysz by assumption.
*/
if (natts == keysz)
return low; /* return first equal key */
}
else
{
+
/*
* There is no equal key. We return either the first greater key
* (which we just found), or the last lesser key.
@@ -524,6 +524,7 @@ _bt_compare(Relation rel,
&& P_LEFTMOST(opaque)
&& offnum == P_HIKEY)
{
+
/*
* we just have to believe that this will only be called with
* offnum == P_HIKEY when P_HIKEY is the OffsetNumber of the first
@@ -702,11 +703,12 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
bool strategyCheck;
ScanKey scankeys = 0;
- int keysCount = 0;
- int *nKeyIs = 0;
- int i, j;
- StrategyNumber strat_total;
-
+ int keysCount = 0;
+ int *nKeyIs = 0;
+ int i,
+ j;
+ StrategyNumber strat_total;
+
rel = scan->relation;
so = (BTScanOpaque) scan->opaque;
@@ -723,15 +725,15 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
_bt_orderkeys(rel, so);
if (so->qual_ok)
- strategyCheck = true;
- }
+ strategyCheck = true;
+ }
strat_total = BTEqualStrategyNumber;
if (strategyCheck)
{
AttrNumber attno;
- nKeyIs = (int *)palloc(so->numberOfKeys*sizeof(int));
- for (i=0; i < so->numberOfKeys; i++)
+ nKeyIs = (int *) palloc(so->numberOfKeys * sizeof(int));
+ for (i = 0; i < so->numberOfKeys; i++)
{
attno = so->keyData[i].sk_attno;
if (attno == keysCount)
@@ -739,16 +741,16 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
if (attno > keysCount + 1)
break;
strat = _bt_getstrat(rel, attno,
- so->keyData[i].sk_procedure);
+ so->keyData[i].sk_procedure);
if (strat == strat_total ||
- strat == BTEqualStrategyNumber)
+ strat == BTEqualStrategyNumber)
{
nKeyIs[keysCount++] = i;
continue;
}
if (ScanDirectionIsBackward(dir) &&
- (strat == BTLessStrategyNumber ||
- strat == BTLessEqualStrategyNumber) )
+ (strat == BTLessStrategyNumber ||
+ strat == BTLessEqualStrategyNumber))
{
nKeyIs[keysCount++] = i;
strat_total = strat;
@@ -757,8 +759,8 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
continue;
}
if (ScanDirectionIsForward(dir) &&
- (strat == BTGreaterStrategyNumber ||
- strat == BTGreaterEqualStrategyNumber) )
+ (strat == BTGreaterStrategyNumber ||
+ strat == BTGreaterEqualStrategyNumber))
{
nKeyIs[keysCount++] = i;
strat_total = strat;
@@ -794,8 +796,8 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
* at the right place in the scan.
*/
/* _bt_orderkeys disallows it, but it's place to add some code latter */
- scankeys = (ScanKey)palloc(keysCount*sizeof(ScanKeyData));
- for (i=0; i < keysCount; i++)
+ scankeys = (ScanKey) palloc(keysCount * sizeof(ScanKeyData));
+ for (i = 0; i < keysCount; i++)
{
j = nKeyIs[i];
if (so->keyData[j].sk_flags & SK_ISNULL)
@@ -804,12 +806,13 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
pfree(scankeys);
elog(ERROR, "_bt_first: btree doesn't support is(not)null, yet");
return ((RetrieveIndexResult) NULL);
- }
- proc = index_getprocid(rel, i+1, BTORDER_PROC);
- ScanKeyEntryInitialize(scankeys+i, so->keyData[j].sk_flags,
- i+1, proc, so->keyData[j].sk_argument);
+ }
+ proc = index_getprocid(rel, i + 1, BTORDER_PROC);
+ ScanKeyEntryInitialize(scankeys + i, so->keyData[j].sk_flags,
+ i + 1, proc, so->keyData[j].sk_argument);
}
- if (nKeyIs) pfree(nKeyIs);
+ if (nKeyIs)
+ pfree(nKeyIs);
stack = _bt_search(rel, keysCount, scankeys, &buf);
_bt_freestack(stack);
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-15 08:42:48 +0000