Esempio n. 1
0
static IndexTuple
BTSpoolGetNextItem(BTSpool *spool, IndexTuple itup, bool *should_free)
{
	if (*should_free)
		pfree(itup);
	return tuplesort_getindextuple(spool->sortstate, true, should_free);
}
Esempio n. 2
0
/*
 * given a spool loaded by successive calls to _h_spool,
 * create an entire index.
 */
void
_h_indexbuild(HSpool *hspool, Relation heapRel)
{
	IndexTuple	itup;
#ifdef USE_ASSERT_CHECKING
	uint32		hashkey = 0;
#endif

	tuplesort_performsort(hspool->sortstate);

	while ((itup = tuplesort_getindextuple(hspool->sortstate, true)) != NULL)
	{
		/*
		 * Technically, it isn't critical that hash keys be found in sorted
		 * order, since this sorting is only used to increase locality of
		 * access as a performance optimization.  It still seems like a good
		 * idea to test tuplesort.c's handling of hash index tuple sorts
		 * through an assertion, though.
		 */
#ifdef USE_ASSERT_CHECKING
		uint32		lasthashkey = hashkey;

		hashkey = _hash_get_indextuple_hashkey(itup) & hspool->hash_mask;
		Assert(hashkey >= lasthashkey);
#endif

		_hash_doinsert(hspool->index, itup, heapRel);
	}
}
Esempio n. 3
0
/*
 * given a spool loaded by successive calls to _h_spool,
 * create an entire index.
 */
void
_h_indexbuild(HSpool *hspool)
{
	IndexTuple	itup;
	bool		should_free;

	tuplesort_performsort(hspool->sortstate);

	while ((itup = tuplesort_getindextuple(hspool->sortstate,
										   true, &should_free)) != NULL)
	{
		_hash_doinsert(hspool->index, itup);
		if (should_free)
			pfree(itup);
	}
}
Esempio n. 4
0
/*
 * Read tuples in correct sort order from tuplesort, and load them into
 * btree leaves.
 */
static void
_bt_load(BTWriteState *wstate, BTSpool *btspool, BTSpool *btspool2)
{
	BTPageState *state = NULL;
	bool		merge = (btspool2 != NULL);
	IndexTuple	itup,
				itup2 = NULL;
	bool		load1;
	TupleDesc	tupdes = RelationGetDescr(wstate->index);
	int			i,
				keysz = RelationGetNumberOfAttributes(wstate->index);
	ScanKey		indexScanKey = NULL;
	SortSupport sortKeys;

	if (merge)
	{
		/*
		 * Another BTSpool for dead tuples exists. Now we have to merge
		 * btspool and btspool2.
		 */

		/* the preparation of merge */
		itup = tuplesort_getindextuple(btspool->sortstate, true);
		itup2 = tuplesort_getindextuple(btspool2->sortstate, true);
		indexScanKey = _bt_mkscankey_nodata(wstate->index);

		/* Prepare SortSupport data for each column */
		sortKeys = (SortSupport) palloc0(keysz * sizeof(SortSupportData));

		for (i = 0; i < keysz; i++)
		{
			SortSupport sortKey = sortKeys + i;
			ScanKey		scanKey = indexScanKey + i;
			int16		strategy;

			sortKey->ssup_cxt = CurrentMemoryContext;
			sortKey->ssup_collation = scanKey->sk_collation;
			sortKey->ssup_nulls_first =
				(scanKey->sk_flags & SK_BT_NULLS_FIRST) != 0;
			sortKey->ssup_attno = scanKey->sk_attno;
			/* Abbreviation is not supported here */
			sortKey->abbreviate = false;

			AssertState(sortKey->ssup_attno != 0);

			strategy = (scanKey->sk_flags & SK_BT_DESC) != 0 ?
				BTGreaterStrategyNumber : BTLessStrategyNumber;

			PrepareSortSupportFromIndexRel(wstate->index, strategy, sortKey);
		}

		_bt_freeskey(indexScanKey);

		for (;;)
		{
			load1 = true;		/* load BTSpool next ? */
			if (itup2 == NULL)
			{
				if (itup == NULL)
					break;
			}
			else if (itup != NULL)
			{
				for (i = 1; i <= keysz; i++)
				{
					SortSupport entry;
					Datum		attrDatum1,
								attrDatum2;
					bool		isNull1,
								isNull2;
					int32		compare;

					entry = sortKeys + i - 1;
					attrDatum1 = index_getattr(itup, i, tupdes, &isNull1);
					attrDatum2 = index_getattr(itup2, i, tupdes, &isNull2);

					compare = ApplySortComparator(attrDatum1, isNull1,
												  attrDatum2, isNull2,
												  entry);
					if (compare > 0)
					{
						load1 = false;
						break;
					}
					else if (compare < 0)
						break;
				}
			}
			else
				load1 = false;

			/* When we see first tuple, create first index page */
			if (state == NULL)
				state = _bt_pagestate(wstate, 0);

			if (load1)
			{
				_bt_buildadd(wstate, state, itup);
				itup = tuplesort_getindextuple(btspool->sortstate, true);
			}
			else
			{
				_bt_buildadd(wstate, state, itup2);
				itup2 = tuplesort_getindextuple(btspool2->sortstate, true);
			}
		}
		pfree(sortKeys);
	}
	else
	{
		/* merge is unnecessary */
		while ((itup = tuplesort_getindextuple(btspool->sortstate,
											   true)) != NULL)
		{
			/* When we see first tuple, create first index page */
			if (state == NULL)
				state = _bt_pagestate(wstate, 0);

			_bt_buildadd(wstate, state, itup);
		}
	}

	/* Close down final pages and write the metapage */
	_bt_uppershutdown(wstate, state);

	/*
	 * If the index is WAL-logged, we must fsync it down to disk before it's
	 * safe to commit the transaction.  (For a non-WAL-logged index we don't
	 * care since the index will be uninteresting after a crash anyway.)
	 *
	 * It's obvious that we must do this when not WAL-logging the build. It's
	 * less obvious that we have to do it even if we did WAL-log the index
	 * pages.  The reason is that since we're building outside shared buffers,
	 * a CHECKPOINT occurring during the build has no way to flush the
	 * previously written data to disk (indeed it won't know the index even
	 * exists).  A crash later on would replay WAL from the checkpoint,
	 * therefore it wouldn't replay our earlier WAL entries. If we do not
	 * fsync those pages here, they might still not be on disk when the crash
	 * occurs.
	 */
	if (RelationNeedsWAL(wstate->index))
	{
		RelationOpenSmgr(wstate->index);
		smgrimmedsync(wstate->index->rd_smgr, MAIN_FORKNUM);
	}
}
Esempio n. 5
0
/*
 * Read tuples in correct sort order from tuplesort, and load them into
 * btree leaves.
 */
static void
_bt_load(BTWriteState *wstate, BTSpool *btspool, BTSpool *btspool2)
{
	BTPageState *state = NULL;
	bool		merge = (btspool2 != NULL);
	IndexTuple	itup,
				itup2 = NULL;
	bool		should_free,
				should_free2,
				load1;
	TupleDesc	tupdes = RelationGetDescr(wstate->index);
	int			i,
				keysz = RelationGetNumberOfAttributes(wstate->index);
	ScanKey		indexScanKey = NULL;

	if (merge)
	{
		/*
		 * Another BTSpool for dead tuples exists. Now we have to merge
		 * btspool and btspool2.
		 */

		/* the preparation of merge */
		itup = tuplesort_getindextuple(btspool->sortstate,
									   true, &should_free);
		itup2 = tuplesort_getindextuple(btspool2->sortstate,
										true, &should_free2);
		indexScanKey = _bt_mkscankey_nodata(wstate->index);

		for (;;)
		{
			load1 = true;		/* load BTSpool next ? */
			if (itup2 == NULL)
			{
				if (itup == NULL)
					break;
			}
			else if (itup != NULL)
			{
				for (i = 1; i <= keysz; i++)
				{
					ScanKey		entry;
					Datum		attrDatum1,
								attrDatum2;
					bool		isNull1,
								isNull2;
					int32		compare;

					entry = indexScanKey + i - 1;
					attrDatum1 = index_getattr(itup, i, tupdes, &isNull1);
					attrDatum2 = index_getattr(itup2, i, tupdes, &isNull2);
					if (isNull1)
					{
						if (isNull2)
							compare = 0;		/* NULL "=" NULL */
						else if (entry->sk_flags & SK_BT_NULLS_FIRST)
							compare = -1;		/* NULL "<" NOT_NULL */
						else
							compare = 1;		/* NULL ">" NOT_NULL */
					}
					else if (isNull2)
					{
						if (entry->sk_flags & SK_BT_NULLS_FIRST)
							compare = 1;		/* NOT_NULL ">" NULL */
						else
							compare = -1;		/* NOT_NULL "<" NULL */
					}
					else
					{
						compare =
							DatumGetInt32(FunctionCall2Coll(&entry->sk_func,
														 entry->sk_collation,
															attrDatum1,
															attrDatum2));

						if (entry->sk_flags & SK_BT_DESC)
							compare = -compare;
					}
					if (compare > 0)
					{
						load1 = false;
						break;
					}
					else if (compare < 0)
						break;
				}
			}
			else
				load1 = false;

			/* When we see first tuple, create first index page */
			if (state == NULL)
				state = _bt_pagestate(wstate, 0);

			if (load1)
			{
				_bt_buildadd(wstate, state, itup);
				if (should_free)
					pfree(itup);
				itup = tuplesort_getindextuple(btspool->sortstate,
											   true, &should_free);
			}
			else
			{
				_bt_buildadd(wstate, state, itup2);
				if (should_free2)
					pfree(itup2);
				itup2 = tuplesort_getindextuple(btspool2->sortstate,
												true, &should_free2);
			}
		}
		_bt_freeskey(indexScanKey);
	}
	else
	{
		/* merge is unnecessary */
		while ((itup = tuplesort_getindextuple(btspool->sortstate,
											   true, &should_free)) != NULL)
		{
			/* When we see first tuple, create first index page */
			if (state == NULL)
				state = _bt_pagestate(wstate, 0);

			_bt_buildadd(wstate, state, itup);
			if (should_free)
				pfree(itup);
		}
	}

	/* Close down final pages and write the metapage */
	_bt_uppershutdown(wstate, state);

	/*
	 * If the index is WAL-logged, we must fsync it down to disk before it's
	 * safe to commit the transaction.	(For a non-WAL-logged index we don't
	 * care since the index will be uninteresting after a crash anyway.)
	 *
	 * It's obvious that we must do this when not WAL-logging the build. It's
	 * less obvious that we have to do it even if we did WAL-log the index
	 * pages.  The reason is that since we're building outside shared buffers,
	 * a CHECKPOINT occurring during the build has no way to flush the
	 * previously written data to disk (indeed it won't know the index even
	 * exists).  A crash later on would replay WAL from the checkpoint,
	 * therefore it wouldn't replay our earlier WAL entries. If we do not
	 * fsync those pages here, they might still not be on disk when the crash
	 * occurs.
	 */
	if (RelationNeedsWAL(wstate->index))
	{
		RelationOpenSmgr(wstate->index);
		smgrimmedsync(wstate->index->rd_smgr, MAIN_FORKNUM);
	}
}