postgresql/contrib/pg_trgm/trgm_gin.c
2007-11-15 21:14:46 +00:00

78 lines
1.6 KiB
C

#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);
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;
int4 trglen;
*nentries = 0;
trg = generate_trgm(VARDATA(val), VARSIZE(val) - VARHDRSZ);
trglen = ARRNELEM(trg);
if (trglen > 0)
{
trgm *ptr;
int4 i = 0,
item;
*nentries = (int32) trglen;
entries = (Datum *) palloc(sizeof(Datum) * trglen);
ptr = GETARR(trg);
while (ptr - GETARR(trg) < ARRNELEM(trg))
{
item = TRGMINT(ptr);
entries[i++] = Int32GetDatum(item);
ptr++;
}
}
PG_RETURN_POINTER(entries);
}
Datum
gin_trgm_consistent(PG_FUNCTION_ARGS)
{
bool *check = (bool *) PG_GETARG_POINTER(0);
text *query = (text *) PG_GETARG_TEXT_P(2);
bool res = FALSE;
TRGM *trg;
int4 i,
trglen,
ntrue = 0;
trg = generate_trgm(VARDATA(query), VARSIZE(query) - VARHDRSZ);
trglen = ARRNELEM(trg);
for (i = 0; i < trglen; i++)
if (check[i])
ntrue++;
#ifdef DIVUNION
res = (trglen == ntrue) ? true : ((((((float4) ntrue) / ((float4) (trglen - ntrue)))) >= trgm_limit) ? true : false);
#else
res = (trglen == 0) ? false : ((((((float4) ntrue) / ((float4) trglen))) >= trgm_limit) ? true : false);
#endif
PG_RETURN_BOOL(res);
}