postgresql/contrib/pg_trgm/trgm_gin.c
Tom Lane 87b8db3774 Adjust the APIs for GIN opclass support functions to allow the extractQuery()
method to pass extra data to the consistent() and comparePartial() methods.
This is the core infrastructure needed to support the soon-to-appear
contrib/btree_gin module.  The APIs are still upward compatible with the
definitions used in 8.3 and before, although *not* with the previous 8.4devel
function definitions.

catversion bump for changes in pg_proc entries (although these are just
cosmetic, since GIN doesn't actually look at the function signature before
calling it...)

Teodor Sigaev and Oleg Bartunov
2009-03-25 22:19:02 +00:00

97 lines
2.1 KiB
C

/*
* $PostgreSQL: pgsql/contrib/pg_trgm/trgm_gin.c,v 1.7 2009/03/25 22:19:01 tgl Exp $
*/
#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 = trgm2int(ptr);
entries[i++] = Int32GetDatum(item);
ptr++;
}
if (PG_NARGS() > 4)
{
/*
* Function called from query extracting
*/
Pointer **extra_data = (Pointer **) PG_GETARG_POINTER(4);
*extra_data = (Pointer*) palloc0(sizeof(Pointer)*(*nentries));
*(int32*)(*extra_data) = trglen;
}
}
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;
int4 i,
trglen,
ntrue = 0;
/* All cases served by this function are inexact */
*recheck = true;
trglen = *(int32*)extra_data;
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);
}