diff options
Diffstat (limited to 'src/backend/access/gist/gist.c')
| -rw-r--r-- | src/backend/access/gist/gist.c | 85 |
1 files changed, 79 insertions, 6 deletions
diff --git a/src/backend/access/gist/gist.c b/src/backend/access/gist/gist.c index 4d595ca9877..0fc21e36c90 100644 --- a/src/backend/access/gist/gist.c +++ b/src/backend/access/gist/gist.c @@ -8,7 +8,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/access/gist/gist.c,v 1.105.4.1 2005/08/30 08:36:52 teodor Exp $ + * $Header: /cvsroot/pgsql/src/backend/access/gist/gist.c,v 1.105.4.2 2009/04/07 17:49:40 teodor Exp $ * *------------------------------------------------------------------------- */ @@ -1212,6 +1212,66 @@ gistadjsubkey(Relation r, } /* + * 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, bytea *entryvec, GIST_SPLITVEC *v) +{ + OffsetNumber i, + maxoff; + int nbytes; + bytea *evec; + char *storage; + + maxoff = ((VARSIZE(entryvec) - VARHDRSZ) / sizeof(GISTENTRY)) - 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 + */ + + /* workaround for 64-bit: ensure GISTENTRY array is maxaligned */ + storage = (char *) palloc(VARSIZE(entryvec) + MAXALIGN(VARHDRSZ)); + evec = (bytea *) (storage + MAXALIGN(VARHDRSZ) - VARHDRSZ); + + VARATT_SIZEP(evec) = v->spl_nleft * sizeof(GISTENTRY) + VARHDRSZ; + memcpy(VARDATA(evec), ((GISTENTRY *) VARDATA(entryvec)) + FirstOffsetNumber, + sizeof(GISTENTRY) * v->spl_nleft); + v->spl_ldatum = FunctionCall2(&giststate->unionFn[0], + PointerGetDatum(evec), + PointerGetDatum(&nbytes)); + + VARATT_SIZEP(evec) = v->spl_nright * sizeof(GISTENTRY) + VARHDRSZ; + memcpy(VARDATA(evec), ((GISTENTRY *) VARDATA(entryvec)) + FirstOffsetNumber + v->spl_nleft, + sizeof(GISTENTRY) * v->spl_nright); + v->spl_rdatum = FunctionCall2(&giststate->unionFn[0], + PointerGetDatum(evec), + PointerGetDatum(&nbytes)); +} + +/* * gistSplit -- split a page in the tree. */ static IndexTuple * @@ -1299,11 +1359,24 @@ gistSplit(Relation r, PointerGetDatum(entryvec), PointerGetDatum(&v)); - /* compatibility with old code */ - if (v.spl_left[v.spl_nleft - 1] == InvalidOffsetNumber) - v.spl_left[v.spl_nleft - 1] = (OffsetNumber) *len; - if (v.spl_right[v.spl_nright - 1] == InvalidOffsetNumber) - v.spl_right[v.spl_nright - 1] = (OffsetNumber) *len; + if ( v.spl_nleft == 0 || v.spl_nright == 0 ) + { + ereport(DEBUG1, + (errcode(ERRCODE_INTERNAL_ERROR), + errmsg("Picksplit method for first column of index \"%s\" failed", + 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"))); + + genericPickSplit(giststate, entryvec, &v); + } + else + { + /* compatibility with old code */ + if (v.spl_left[v.spl_nleft - 1] == InvalidOffsetNumber) + v.spl_left[v.spl_nleft - 1] = (OffsetNumber) *len; + if (v.spl_right[v.spl_nright - 1] == InvalidOffsetNumber) + v.spl_right[v.spl_nright - 1] = (OffsetNumber) *len; + } v.spl_lattr[0] = v.spl_ldatum; v.spl_rattr[0] = v.spl_rdatum; |