postgresql/contrib/pg_trgm/trgm_gin.c

91 lines
1.9 KiB
C

/*
* contrib/pg_trgm/trgm_gin.c
*/
#include "postgres.h"
#include "trgm.h"
#include "access/gin.h"
#include "access/itup.h"
#include "access/tuptoaster.h"
#include "storage/bufpage.h"
#include "utils/array.h"
#include "utils/builtins.h"
PG_FUNCTION_INFO_V1(gin_extract_trgm);
Datum gin_extract_trgm(PG_FUNCTION_ARGS);
PG_FUNCTION_INFO_V1(gin_trgm_consistent);
Datum gin_trgm_consistent(PG_FUNCTION_ARGS);
/*
* This function is used as both extractValue and extractQuery
*/
Datum
gin_extract_trgm(PG_FUNCTION_ARGS)
{
text *val = (text *) PG_GETARG_TEXT_P(0);
int32 *nentries = (int32 *) PG_GETARG_POINTER(1);
Datum *entries = NULL;
TRGM *trg;
int32 trglen;
*nentries = 0;
trg = generate_trgm(VARDATA(val), VARSIZE(val) - VARHDRSZ);
trglen = ARRNELEM(trg);
if (trglen > 0)
{
trgm *ptr;
int32 i;
*nentries = trglen;
entries = (Datum *) palloc(sizeof(Datum) * trglen);
ptr = GETARR(trg);
for (i = 0; i < trglen; i++)
{
int32 item = trgm2int(ptr);
entries[i] = Int32GetDatum(item);
ptr++;
}
}
PG_RETURN_POINTER(entries);
}
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 = FALSE;
int32 i,
ntrue = 0;
/* All cases served by this function are inexact */
*recheck = true;
/* Count the matches */
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
PG_RETURN_BOOL(res);
}