/*
* Insert one or more heap TIDs associated with the given key value.
* This will either add a single key entry, or enlarge a pre-existing entry.
*
* During an index build, buildStats is non-null and the counters
* it contains should be incremented as needed.
*/
void
ginEntryInsert(GinState *ginstate,
OffsetNumber attnum, Datum key, GinNullCategory category,
ItemPointerData *items, uint32 nitem,
GinStatsData *buildStats)
{
GinBtreeData btree;
GinBtreeStack *stack;
IndexTuple itup;
Page page;
/* During index build, count the to-be-inserted entry */
if (buildStats)
buildStats->nEntries++;
ginPrepareEntryScan(&btree, attnum, key, category, ginstate);
stack = ginFindLeafPage(&btree, GIN_ROOT_BLKNO, false);
page = BufferGetPage(stack->buffer);
if (btree.findItem(&btree, stack))
{
/* found pre-existing entry */
itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, stack->off));
if (GinIsPostingTree(itup))
{
/* add entries to existing posting tree */
BlockNumber rootPostingTree = GinGetPostingTree(itup);
/* release all stack */
LockBuffer(stack->buffer, GIN_UNLOCK);
freeGinBtreeStack(stack);
/* insert into posting tree */
ginInsertItemPointers(ginstate->index, rootPostingTree,
items, nitem,
buildStats);
return;
}
/* modify an existing leaf entry */
itup = addItemPointersToLeafTuple(ginstate, itup,
items, nitem, buildStats);
btree.isDelete = TRUE;
}
else
{
/* no match, so construct a new leaf entry */
itup = buildFreshLeafTuple(ginstate, attnum, key, category,
items, nitem, buildStats);
}
/* Insert the new or modified leaf tuple */
btree.entry = itup;
ginInsertValue(&btree, stack, buildStats);
pfree(itup);
}
/*
* Adds array of item pointers to tuple's posting list, or
* creates posting tree and tuple pointing to tree in case
* of not enough space. Max size of tuple is defined in
* GinFormTuple(). Returns a new, modified index tuple.
* items[] must be in sorted order with no duplicates.
*/
static IndexTuple
addItemPointersToLeafTuple(GinState *ginstate,
IndexTuple old,
ItemPointerData *items, uint32 nitem,
GinStatsData *buildStats, Buffer buffer)
{
OffsetNumber attnum;
Datum key;
GinNullCategory category;
IndexTuple res;
ItemPointerData *newItems,
*oldItems;
int oldNPosting,
newNPosting;
GinPostingList *compressedList;
Assert(!GinIsPostingTree(old));
attnum = gintuple_get_attrnum(ginstate, old);
key = gintuple_get_key(ginstate, old, &category);
/* merge the old and new posting lists */
oldItems = ginReadTuple(ginstate, attnum, old, &oldNPosting);
newItems = ginMergeItemPointers(items, nitem,
oldItems, oldNPosting,
&newNPosting);
/* Compress the posting list, and try to a build tuple with room for it */
res = NULL;
compressedList = ginCompressPostingList(newItems, newNPosting, GinMaxItemSize,
NULL);
pfree(newItems);
if (compressedList)
{
res = GinFormTuple(ginstate, attnum, key, category,
(char *) compressedList,
SizeOfGinPostingList(compressedList),
newNPosting,
false);
pfree(compressedList);
}
if (!res)
{
/* posting list would be too big, convert to posting tree */
BlockNumber postingRoot;
/*
* Initialize posting tree with the old tuple's posting list. It's
* surely small enough to fit on one posting-tree page, and should
* already be in order with no duplicates.
*/
postingRoot = createPostingTree(ginstate->index,
oldItems,
oldNPosting,
buildStats,
buffer);
/* Now insert the TIDs-to-be-added into the posting tree */
ginInsertItemPointers(ginstate->index, postingRoot,
items, nitem,
buildStats);
/* And build a new posting-tree-only result tuple */
res = GinFormTuple(ginstate, attnum, key, category, NULL, 0, 0, true);
GinSetPostingTree(res, postingRoot);
}
pfree(oldItems);
return res;
}
/*
* Adds array of item pointers to tuple's posting list, or
* creates posting tree and tuple pointing to tree in case
* of not enough space. Max size of tuple is defined in
* GinFormTuple(). Returns a new, modified index tuple.
* items[] must be in sorted order with no duplicates.
*/
static IndexTuple
addItemPointersToLeafTuple(GinState *ginstate,
IndexTuple old,
ItemPointerData *items, uint32 nitem,
GinStatsData *buildStats)
{
OffsetNumber attnum;
Datum key;
GinNullCategory category;
IndexTuple res;
Assert(!GinIsPostingTree(old));
attnum = gintuple_get_attrnum(ginstate, old);
key = gintuple_get_key(ginstate, old, &category);
/* try to build tuple with room for all the items */
res = GinFormTuple(ginstate, attnum, key, category,
NULL, nitem + GinGetNPosting(old),
false);
if (res)
{
/* good, small enough */
uint32 newnitem;
/* fill in the posting list with union of old and new TIDs */
newnitem = ginMergeItemPointers(GinGetPosting(res),
GinGetPosting(old),
GinGetNPosting(old),
items, nitem);
/* merge might have eliminated some duplicate items */
GinShortenTuple(res, newnitem);
}
else
{
/* posting list would be too big, convert to posting tree */
BlockNumber postingRoot;
/*
* Initialize posting tree with the old tuple's posting list. It's
* surely small enough to fit on one posting-tree page, and should
* already be in order with no duplicates.
*/
postingRoot = createPostingTree(ginstate->index,
GinGetPosting(old),
GinGetNPosting(old),
buildStats);
/* Now insert the TIDs-to-be-added into the posting tree */
ginInsertItemPointers(ginstate->index, postingRoot,
items, nitem,
buildStats);
/* And build a new posting-tree-only result tuple */
res = GinFormTuple(ginstate, attnum, key, category, NULL, 0, true);
GinSetPostingTree(res, postingRoot);
}
return res;
}
/*
* Creates new posting tree containing the given TIDs. Returns the page
* number of the root of the new posting tree.
*
* items[] must be in sorted order with no duplicates.
*/
BlockNumber
createPostingTree(Relation index, ItemPointerData *items, uint32 nitems,
GinStatsData *buildStats)
{
BlockNumber blkno;
Buffer buffer;
Page page;
int nrootitems;
/* Calculate how many TIDs will fit on first page. */
nrootitems = Min(nitems, GinMaxLeafDataItems);
/*
* Create the root page.
*/
buffer = GinNewBuffer(index);
page = BufferGetPage(buffer);
blkno = BufferGetBlockNumber(buffer);
START_CRIT_SECTION();
GinInitBuffer(buffer, GIN_DATA | GIN_LEAF);
memcpy(GinDataPageGetData(page), items, sizeof(ItemPointerData) * nrootitems);
GinPageGetOpaque(page)->maxoff = nrootitems;
MarkBufferDirty(buffer);
if (RelationNeedsWAL(index))
{
XLogRecPtr recptr;
XLogRecData rdata[2];
ginxlogCreatePostingTree data;
data.node = index->rd_node;
data.blkno = blkno;
data.nitem = nrootitems;
rdata[0].buffer = InvalidBuffer;
rdata[0].data = (char *) &data;
rdata[0].len = sizeof(ginxlogCreatePostingTree);
rdata[0].next = &rdata[1];
rdata[1].buffer = InvalidBuffer;
rdata[1].data = (char *) items;
rdata[1].len = sizeof(ItemPointerData) * nrootitems;
rdata[1].next = NULL;
recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_CREATE_PTREE, rdata);
PageSetLSN(page, recptr);
}
UnlockReleaseBuffer(buffer);
END_CRIT_SECTION();
/* During index build, count the newly-added data page */
if (buildStats)
buildStats->nDataPages++;
/*
* Add any remaining TIDs to the newly-created posting tree.
*/
if (nitems > nrootitems)
{
ginInsertItemPointers(index, blkno,
items + nrootitems,
nitems - nrootitems,
buildStats);
}
return blkno;
}