コード例 #1
0
ファイル: trgm_gin.c プロジェクト: 5A68656E67/postgres
/*
 * In all cases, GIN_TRUE is at least as favorable to inclusion as
 * GIN_MAYBE. If no better option is available, simply treat
 * GIN_MAYBE as if it were GIN_TRUE and apply the same test as the binary
 * consistent function.
 */
Datum
gin_trgm_triconsistent(PG_FUNCTION_ARGS)
{
	GinTernaryValue  *check = (GinTernaryValue *) PG_GETARG_POINTER(0);
	StrategyNumber strategy = PG_GETARG_UINT16(1);

	/* text    *query = PG_GETARG_TEXT_P(2); */
	int32		nkeys = PG_GETARG_INT32(3);
	Pointer    *extra_data = (Pointer *) PG_GETARG_POINTER(4);
	GinTernaryValue	res = GIN_MAYBE;
	int32		i,
				ntrue;
	bool	   *boolcheck;

	switch (strategy)
	{
		case SimilarityStrategyNumber:
			/* Count the matches */
			ntrue = 0;
			for (i = 0; i < nkeys; i++)
			{
				if (check[i] != GIN_FALSE)
					ntrue++;
			}

			/*
			 * See comment in gin_trgm_consistent() about * upper bound formula
			 */
			res = (nkeys == 0) ? GIN_FALSE : (((((float4) ntrue) / ((float4) nkeys)) >= trgm_limit) ? GIN_MAYBE : GIN_FALSE);
			break;
		case ILikeStrategyNumber:
#ifndef IGNORECASE
			elog(ERROR, "cannot handle ~~* with case-sensitive trigrams");
#endif
			/* FALL THRU */
		case LikeStrategyNumber:
			/* Check if all extracted trigrams are presented. */
			res = GIN_MAYBE;
			for (i = 0; i < nkeys; i++)
			{
				if (check[i] == GIN_FALSE)
				{
					res = GIN_FALSE;
					break;
				}
			}
			break;
		case RegExpICaseStrategyNumber:
#ifndef IGNORECASE
			elog(ERROR, "cannot handle ~* with case-sensitive trigrams");
#endif
			/* FALL THRU */
		case RegExpStrategyNumber:
			if (nkeys < 1)
			{
				/* Regex processing gave no result: do full index scan */
				res = GIN_MAYBE;
			}
			else
			{
				/*
				 * As trigramsMatchGraph implements a montonic boolean function,
				 * promoting all GIN_MAYBE keys to GIN_TRUE will give a
				 * conservative result.
				 */
				boolcheck = (bool *) palloc(sizeof(bool) * nkeys);
				for (i = 0; i < nkeys; i++)
					boolcheck[i] = (check[i] != GIN_FALSE);
				if (!trigramsMatchGraph((TrgmPackedGraph *) extra_data[0],
										boolcheck))
					res = GIN_FALSE;
				pfree(boolcheck);
			}
			break;
		default:
			elog(ERROR, "unrecognized strategy number: %d", strategy);
			res = GIN_FALSE;		/* keep compiler quiet */
			break;
	}

	/* All cases served by this function are inexact */
	Assert(res != GIN_TRUE);
	PG_RETURN_GIN_TERNARY_VALUE(res);
}
コード例 #2
0
Datum
gin_trgm_consistent(PG_FUNCTION_ARGS)
{
	bool	   *check = (bool *) PG_GETARG_POINTER(0);
	StrategyNumber strategy = PG_GETARG_UINT16(1);

	/* text    *query = PG_GETARG_TEXT_P(2); */
	int32		nkeys = PG_GETARG_INT32(3);
	Pointer    *extra_data = (Pointer *) PG_GETARG_POINTER(4);
	bool	   *recheck = (bool *) PG_GETARG_POINTER(5);
	bool		res;
	int32		i,
				ntrue;

	/* All cases served by this function are inexact */
	*recheck = true;

	switch (strategy)
	{
		case SimilarityStrategyNumber:
			/* Count the matches */
			ntrue = 0;
			for (i = 0; i < nkeys; i++)
			{
				if (check[i])
					ntrue++;
			}
#ifdef DIVUNION
			res = (nkeys == ntrue) ? true : ((((((float4) ntrue) / ((float4) (nkeys - ntrue)))) >= trgm_limit) ? true : false);
#else
			res = (nkeys == 0) ? false : ((((((float4) ntrue) / ((float4) nkeys))) >= trgm_limit) ? true : false);
#endif
			break;
		case ILikeStrategyNumber:
#ifndef IGNORECASE
			elog(ERROR, "cannot handle ~~* with case-sensitive trigrams");
#endif
			/* FALL THRU */
		case LikeStrategyNumber:
			/* Check if all extracted trigrams are presented. */
			res = true;
			for (i = 0; i < nkeys; i++)
			{
				if (!check[i])
				{
					res = false;
					break;
				}
			}
			break;
		case RegExpICaseStrategyNumber:
#ifndef IGNORECASE
			elog(ERROR, "cannot handle ~* with case-sensitive trigrams");
#endif
			/* FALL THRU */
		case RegExpStrategyNumber:
			if (nkeys < 1)
			{
				/* Regex processing gave no result: do full index scan */
				res = true;
			}
			else
				res = trigramsMatchGraph((TrgmPackedGraph *) extra_data[0],
										 check);
			break;
		default:
			elog(ERROR, "unrecognized strategy number: %d", strategy);
			res = false;		/* keep compiler quiet */
			break;
	}

	PG_RETURN_BOOL(res);
}
コード例 #3
0
ファイル: trgm_gin.c プロジェクト: 5A68656E67/postgres
Datum
gin_trgm_consistent(PG_FUNCTION_ARGS)
{
	bool	   *check = (bool *) PG_GETARG_POINTER(0);
	StrategyNumber strategy = PG_GETARG_UINT16(1);

	/* text    *query = PG_GETARG_TEXT_P(2); */
	int32		nkeys = PG_GETARG_INT32(3);
	Pointer    *extra_data = (Pointer *) PG_GETARG_POINTER(4);
	bool	   *recheck = (bool *) PG_GETARG_POINTER(5);
	bool		res;
	int32		i,
				ntrue;

	/* All cases served by this function are inexact */
	*recheck = true;

	switch (strategy)
	{
		case SimilarityStrategyNumber:
			/* Count the matches */
			ntrue = 0;
			for (i = 0; i < nkeys; i++)
			{
				if (check[i])
					ntrue++;
			}

			/*--------------------
			 * If DIVUNION is defined then similarity formula is:
			 * c / (len1 + len2 - c)
			 * where c is number of common trigrams and it stands as ntrue in
			 * this code.  Here we don't know value of len2 but we can assume
			 * that c (ntrue) is a lower bound of len2, so upper bound of
			 * similarity is:
			 * c / (len1 + c - c)  => c / len1
			 * If DIVUNION is not defined then similarity formula is:
			 * c / max(len1, len2)
			 * And again, c (ntrue) is a lower bound of len2, but c <= len1
			 * just by definition and, consequently, upper bound of
			 * similarity is just c / len1.
			 * So, independly on DIVUNION the upper bound formula is the same.
			 */
			res = (nkeys == 0) ? false : ((((((float4) ntrue) / ((float4) nkeys))) >= trgm_limit) ? true : false);
			break;
		case ILikeStrategyNumber:
#ifndef IGNORECASE
			elog(ERROR, "cannot handle ~~* with case-sensitive trigrams");
#endif
			/* FALL THRU */
		case LikeStrategyNumber:
			/* Check if all extracted trigrams are presented. */
			res = true;
			for (i = 0; i < nkeys; i++)
			{
				if (!check[i])
				{
					res = false;
					break;
				}
			}
			break;
		case RegExpICaseStrategyNumber:
#ifndef IGNORECASE
			elog(ERROR, "cannot handle ~* with case-sensitive trigrams");
#endif
			/* FALL THRU */
		case RegExpStrategyNumber:
			if (nkeys < 1)
			{
				/* Regex processing gave no result: do full index scan */
				res = true;
			}
			else
				res = trigramsMatchGraph((TrgmPackedGraph *) extra_data[0],
										 check);
			break;
		default:
			elog(ERROR, "unrecognized strategy number: %d", strategy);
			res = false;		/* keep compiler quiet */
			break;
	}

	PG_RETURN_BOOL(res);
}