/*
* Forms union of oldtup and addtup, if union == oldtup then return NULL
*/
IndexTuple
gistgetadjusted(Relation r, IndexTuple oldtup, IndexTuple addtup, GISTSTATE *giststate)
{
bool neednew = false;
GISTENTRY oldentries[INDEX_MAX_KEYS],
addentries[INDEX_MAX_KEYS];
bool oldisnull[INDEX_MAX_KEYS],
addisnull[INDEX_MAX_KEYS];
Datum attr[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
IndexTuple newtup = NULL;
int i;
gistDeCompressAtt(giststate, r, oldtup, NULL,
(OffsetNumber) 0, oldentries, oldisnull);
gistDeCompressAtt(giststate, r, addtup, NULL,
(OffsetNumber) 0, addentries, addisnull);
for (i = 0; i < r->rd_att->natts; i++)
{
gistMakeUnionKey(giststate, i,
oldentries + i, oldisnull[i],
addentries + i, addisnull[i],
attr + i, isnull + i);
if (neednew)
/* we already need new key, so we can skip check */
continue;
if (isnull[i])
/* union of key may be NULL if and only if both keys are NULL */
continue;
if (!addisnull[i])
{
if (oldisnull[i] ||
!gistKeyIsEQ(giststate, i, oldentries[i].key, attr[i]))
neednew = true;
}
}
if (neednew)
{
/* need to update key */
newtup = gistFormTuple(giststate, r, attr, isnull, false);
newtup->t_tid = oldtup->t_tid;
}
return newtup;
}
/*
* Forms union of oldtup and addtup, if union == oldtup then return NULL
*/
IndexTuple
gistgetadjusted(Relation r, IndexTuple oldtup, IndexTuple addtup, GISTSTATE *giststate)
{
bool neednew = FALSE;
GISTENTRY oldentries[INDEX_MAX_KEYS],
addentries[INDEX_MAX_KEYS];
bool oldisnull[INDEX_MAX_KEYS],
addisnull[INDEX_MAX_KEYS];
IndexTuple newtup = NULL;
int i;
if (GistTupleIsInvalid(oldtup) || GistTupleIsInvalid(addtup))
return gist_form_invalid_tuple(ItemPointerGetBlockNumber(&(oldtup->t_tid)));
gistDeCompressAtt(giststate, r, oldtup, NULL,
(OffsetNumber) 0, oldentries, oldisnull);
gistDeCompressAtt(giststate, r, addtup, NULL,
(OffsetNumber) 0, addentries, addisnull);
for (i = 0; i < r->rd_att->natts; i++)
{
gistMakeUnionKey(giststate, i,
oldentries + i, oldisnull[i],
addentries + i, addisnull[i],
attrS + i, isnullS + i);
if (neednew)
/* we already need new key, so we can skip check */
continue;
if (isnullS[i])
/* union of key may be NULL if and only if both keys are NULL */
continue;
if (!addisnull[i])
{
if (oldisnull[i] || gistKeyIsEQ(giststate, i, oldentries[i].key, attrS[i]) == false)
neednew = true;
}
}
if (neednew)
{
/* need to update key */
newtup = gistFormTuple(giststate, r, attrS, isnullS, false);
newtup->t_tid = oldtup->t_tid;
}
return newtup;
}
/*
* Calls user picksplit method for attno columns to split vector to
* two vectors. May use attno+n columns data to
* get better split.
* Returns TRUE and v->spl_equiv = NULL if left and right unions of attno columns are the same,
* so caller may find better split
* Returns TRUE and v->spl_equiv != NULL if there is tuples which may be freely moved
*/
static bool
gistUserPicksplit(Relation r, GistEntryVector *entryvec, int attno, GistSplitVector *v,
IndexTuple *itup, int len, GISTSTATE *giststate)
{
GIST_SPLITVEC *sv = &v->splitVector;
/*
* now let the user-defined picksplit function set up the split vector; in
* entryvec there is no null value!!
*/
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];
FunctionCall2(&giststate->picksplitFn[attno],
PointerGetDatum(entryvec),
PointerGetDatum(sv));
if ( sv->spl_nleft == 0 || sv->spl_nright == 0 )
{
ereport(DEBUG1,
(errcode(ERRCODE_INTERNAL_ERROR),
errmsg("picksplit method for column %d of index \"%s\" failed",
attno+1, RelationGetRelationName(r)),
errhint("The index is not optimal. To optimize it, contact a developer, or try to use the column as the second one in the CREATE INDEX command.")));
/*
* 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
{
/* 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_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;
v->spl_rattr[attno] = sv->spl_rdatum;
v->spl_lisnull[attno] = false;
v->spl_risnull[attno] = false;
/*
* if index is multikey, then we must to try get smaller bounding box for
* subkey(s)
*/
v->spl_equiv = NULL;
if (giststate->tupdesc->natts > 1 && attno + 1 != giststate->tupdesc->natts)
{
if (gistKeyIsEQ(giststate, attno, sv->spl_ldatum, sv->spl_rdatum))
{
/*
* Left and right key's unions are equial, so we can get better
* split by following columns. Note, unions for attno columns are
* already done.
*/
return true;
}
else
{
int LenEquiv;
v->spl_equiv = (bool *) palloc0(sizeof(bool) * (entryvec->n + 1));
LenEquiv = gistfindgroup(r, giststate, entryvec->vector, v, attno);
/*
* if possible, we should distribute equivalent tuples
*/
if (LenEquiv == 0)
{
gistunionsubkey(giststate, itup, v, attno + 1);
}
else
{
cleanupOffsets(sv->spl_left, &sv->spl_nleft, v->spl_equiv, &LenEquiv);
cleanupOffsets(sv->spl_right, &sv->spl_nright, v->spl_equiv, &LenEquiv);
gistunionsubkey(giststate, itup, v, attno + 1);
if (LenEquiv == 1)
{
/*
* In case with one tuple we just choose left-right by
* penalty. It's simplify user-defined pickSplit
*/
OffsetNumber toMove = InvalidOffsetNumber;
for (toMove = FirstOffsetNumber; toMove < entryvec->n; toMove++)
if (v->spl_equiv[toMove])
break;
Assert(toMove < entryvec->n);
placeOne(r, giststate, v, itup[toMove - 1], toMove, attno + 1);
/*
* redo gistunionsubkey(): it will not degradate
* performance, because it's very rarely
*/
v->spl_equiv = NULL;
gistunionsubkey(giststate, itup, v, attno + 1);
return false;
}
else if (LenEquiv > 1)
return true;
}
}
}
return false;
}
