* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/gist/gistproc.c,v 1.15 2009/01/01 17:23:35 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/gist/gistproc.c,v 1.16 2009/04/06 14:27:27 teodor Exp $
*
*-------------------------------------------------------------------------
*/
}
/*
+ * Trivial split: half of entries will be placed on one page
+ * and another half - to another
+ */
+static void
+fallbackSplit(GistEntryVector *entryvec, GIST_SPLITVEC *v)
+{
+ OffsetNumber i,
+ maxoff;
+ BOX *unionL = NULL,
+ *unionR = NULL;
+ int nbytes;
+
+ maxoff = entryvec->n - 1;
+
+ nbytes = (maxoff + 2) * sizeof(OffsetNumber);
+ v->spl_left = (OffsetNumber *) palloc(nbytes);
+ v->spl_right = (OffsetNumber *) palloc(nbytes);
+ v->spl_nleft = v->spl_nright = 0;
+
+ for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
+ {
+ BOX * cur = DatumGetBoxP(entryvec->vector[i].key);
+
+ if (i <= (maxoff - FirstOffsetNumber + 1) / 2)
+ {
+ v->spl_left[v->spl_nleft] = i;
+ if (unionL == NULL)
+ {
+ unionL = (BOX *) palloc(sizeof(BOX));
+ *unionL = *cur;
+ }
+ else
+ adjustBox(unionL, cur);
+
+ v->spl_nleft++;
+ }
+ else
+ {
+ v->spl_right[v->spl_nright] = i;
+ if (unionR == NULL)
+ {
+ unionR = (BOX *) palloc(sizeof(BOX));
+ *unionR = *cur;
+ }
+ else
+ adjustBox(unionR, cur);
+
+ v->spl_nright++;
+ }
+ }
+
+ if (v->spl_ldatum_exists)
+ adjustBox(unionL, DatumGetBoxP(v->spl_ldatum));
+ v->spl_ldatum = BoxPGetDatum(unionL);
+
+ if (v->spl_rdatum_exists)
+ adjustBox(unionR, DatumGetBoxP(v->spl_rdatum));
+ v->spl_rdatum = BoxPGetDatum(unionR);
+
+ v->spl_ldatum_exists = v->spl_rdatum_exists = false;
+}
+
+/*
* The GiST PickSplit method
*
* New linear algorithm, see 'New Linear Node Splitting Algorithm for R-tree',
adjustBox(&pageunion, cur);
}
- nbytes = (maxoff + 2) * sizeof(OffsetNumber);
- listL = (OffsetNumber *) palloc(nbytes);
- listR = (OffsetNumber *) palloc(nbytes);
- unionL = (BOX *) palloc(sizeof(BOX));
- unionR = (BOX *) palloc(sizeof(BOX));
if (allisequal)
{
- cur = DatumGetBoxP(entryvec->vector[OffsetNumberNext(FirstOffsetNumber)].key);
- if (memcmp((void *) cur, (void *) &pageunion, sizeof(BOX)) == 0)
- {
- v->spl_left = listL;
- v->spl_right = listR;
- v->spl_nleft = v->spl_nright = 0;
- memcpy((void *) unionL, (void *) &pageunion, sizeof(BOX));
- memcpy((void *) unionR, (void *) &pageunion, sizeof(BOX));
-
- for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
- {
- if (i <= (maxoff - FirstOffsetNumber + 1) / 2)
- {
- v->spl_left[v->spl_nleft] = i;
- v->spl_nleft++;
- }
- else
- {
- v->spl_right[v->spl_nright] = i;
- v->spl_nright++;
- }
- }
-
- if (v->spl_ldatum_exists)
- adjustBox(unionL, DatumGetBoxP(v->spl_ldatum));
- v->spl_ldatum = BoxPGetDatum(unionL);
-
- if (v->spl_rdatum_exists)
- adjustBox(unionR, DatumGetBoxP(v->spl_rdatum));
- v->spl_rdatum = BoxPGetDatum(unionR);
-
- v->spl_ldatum_exists = v->spl_rdatum_exists = false;
-
- PG_RETURN_POINTER(v);
- }
+ /*
+ * All entries are the same
+ */
+ fallbackSplit(entryvec, v);
+ PG_RETURN_POINTER(v);
}
+ nbytes = (maxoff + 2) * sizeof(OffsetNumber);
+ listL = (OffsetNumber *) palloc(nbytes);
+ listR = (OffsetNumber *) palloc(nbytes);
listB = (OffsetNumber *) palloc(nbytes);
listT = (OffsetNumber *) palloc(nbytes);
+ unionL = (BOX *) palloc(sizeof(BOX));
+ unionR = (BOX *) palloc(sizeof(BOX));
unionB = (BOX *) palloc(sizeof(BOX));
unionT = (BOX *) palloc(sizeof(BOX));
else
ADDLIST(listT, unionT, posT, i);
}
+
+ if (IS_BADRATIO(posR, posL) && IS_BADRATIO(posT, posB))
+ {
+ fallbackSplit(entryvec, v);
+ PG_RETURN_POINTER(v);
+ }
}
/* which split more optimal? */
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/gist/gistsplit.c,v 1.7 2009/01/01 17:23:35 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/gist/gistsplit.c,v 1.8 2009/04/06 14:27:27 teodor Exp $
*
*-------------------------------------------------------------------------
*/
}
/*
+ * Trivial picksplit implementaion. Function called only
+ * if user-defined picksplit puts all keys to the one page.
+ * That is a bug of user-defined picksplit but we'd like
+ * to "fix" that.
+ */
+static void
+genericPickSplit(GISTSTATE *giststate, GistEntryVector *entryvec, GIST_SPLITVEC *v, int attno)
+{
+ OffsetNumber i,
+ maxoff;
+ int nbytes;
+ GistEntryVector *evec;
+
+ maxoff = entryvec->n - 1;
+
+ nbytes = (maxoff + 2) * sizeof(OffsetNumber);
+
+ v->spl_left = (OffsetNumber *) palloc(nbytes);
+ v->spl_right = (OffsetNumber *) palloc(nbytes);
+ v->spl_nleft = v->spl_nright = 0;
+
+ for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
+ {
+ if (i <= (maxoff - FirstOffsetNumber + 1) / 2)
+ {
+ v->spl_left[v->spl_nleft] = i;
+ v->spl_nleft++;
+ }
+ else
+ {
+ v->spl_right[v->spl_nright] = i;
+ v->spl_nright++;
+ }
+ }
+
+ /*
+ * Form unions of each page
+ */
+
+ evec = palloc( sizeof(GISTENTRY) * entryvec->n + GEVHDRSZ );
+
+ evec->n = v->spl_nleft;
+ memcpy(evec->vector, entryvec->vector + FirstOffsetNumber,
+ sizeof(GISTENTRY) * evec->n);
+ v->spl_ldatum = FunctionCall2(&giststate->unionFn[attno],
+ PointerGetDatum(evec),
+ PointerGetDatum(&nbytes));
+
+ evec->n = v->spl_nright;
+ memcpy(evec->vector, entryvec->vector + FirstOffsetNumber + v->spl_nleft,
+ sizeof(GISTENTRY) * evec->n);
+ v->spl_rdatum = FunctionCall2(&giststate->unionFn[attno],
+ PointerGetDatum(evec),
+ PointerGetDatum(&nbytes));
+}
+
+/*
* Calls user picksplit method for attno columns to split vector to
* two vectors. May use attno+n columns data to
* get better split.
/*
* now let the user-defined picksplit function set up the split vector; in
- * entryvec have no null value!!
+ * entryvec there is no null value!!
*/
sv->spl_ldatum_exists = (v->spl_lisnull[attno]) ? false : true;
PointerGetDatum(entryvec),
PointerGetDatum(sv));
- /* compatibility with old code */
- if (sv->spl_left[sv->spl_nleft - 1] == InvalidOffsetNumber)
- sv->spl_left[sv->spl_nleft - 1] = (OffsetNumber) (entryvec->n - 1);
- if (sv->spl_right[sv->spl_nright - 1] == InvalidOffsetNumber)
- sv->spl_right[sv->spl_nright - 1] = (OffsetNumber) (entryvec->n - 1);
+ if ( sv->spl_nleft == 0 || sv->spl_nright == 0 )
+ {
+ ereport(DEBUG1,
+ (errcode(ERRCODE_INTERNAL_ERROR),
+ errmsg("Picksplit method for %d column of index \"%s\" failed",
+ attno+1, RelationGetRelationName(r)),
+ errhint("Index is not optimal, to optimize it contact developer or try to use the column as a second one in create index command")));
- if (sv->spl_ldatum_exists || sv->spl_rdatum_exists)
+ /*
+ * Reinit GIST_SPLITVEC. Although that fields are not used
+ * by genericPickSplit(), let us set up it for further processing
+ */
+ sv->spl_ldatum_exists = (v->spl_lisnull[attno]) ? false : true;
+ sv->spl_rdatum_exists = (v->spl_risnull[attno]) ? false : true;
+ sv->spl_ldatum = v->spl_lattr[attno];
+ sv->spl_rdatum = v->spl_rattr[attno];
+
+ genericPickSplit(giststate, entryvec, sv, attno);
+
+ if (sv->spl_ldatum_exists || sv->spl_rdatum_exists)
+ supportSecondarySplit(r, giststate, attno, sv, v->spl_lattr[attno], v->spl_rattr[attno]);
+ }
+ else
{
- elog(LOG, "PickSplit method of %d columns of index '%s' doesn't support secondary split",
- attno + 1, RelationGetRelationName(r));
+ /* compatibility with old code */
+ if (sv->spl_left[sv->spl_nleft - 1] == InvalidOffsetNumber)
+ sv->spl_left[sv->spl_nleft - 1] = (OffsetNumber) (entryvec->n - 1);
+ if (sv->spl_right[sv->spl_nright - 1] == InvalidOffsetNumber)
+ sv->spl_right[sv->spl_nright - 1] = (OffsetNumber) (entryvec->n - 1);
- supportSecondarySplit(r, giststate, attno, sv, v->spl_lattr[attno], v->spl_rattr[attno]);
+ if (sv->spl_ldatum_exists || sv->spl_rdatum_exists)
+ {
+ elog(LOG, "PickSplit method of %d columns of index '%s' doesn't support secondary split",
+ attno + 1, RelationGetRelationName(r));
+
+ supportSecondarySplit(r, giststate, attno, sv, v->spl_lattr[attno], v->spl_rattr[attno]);
+ }
}
v->spl_lattr[attno] = sv->spl_ldatum;
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