diff options
Diffstat (limited to 'src/backend/utils/adt/tsquery_gist.c')
| -rw-r--r-- | src/backend/utils/adt/tsquery_gist.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/src/backend/utils/adt/tsquery_gist.c b/src/backend/utils/adt/tsquery_gist.c new file mode 100644 index 0000000000..0deca10075 --- /dev/null +++ b/src/backend/utils/adt/tsquery_gist.c @@ -0,0 +1,259 @@ +/*------------------------------------------------------------------------- + * + * tsquery_gist.c + * GiST index support for tsquery + * + * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group + * + * + * IDENTIFICATION + * $PostgreSQL: pgsql/src/backend/utils/adt/tsquery_gist.c,v 1.1 2007/08/21 01:11:19 tgl Exp $ + * + *------------------------------------------------------------------------- + */ + +#include "postgres.h" + +#include "access/skey.h" +#include "access/gist.h" +#include "tsearch/ts_type.h" +#include "tsearch/ts_utils.h" + +#define GETENTRY(vec,pos) ((TSQuerySign *) DatumGetPointer((vec)->vector[(pos)].key)) + +Datum +gtsquery_compress(PG_FUNCTION_ARGS) +{ + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); + GISTENTRY *retval = entry; + + if (entry->leafkey) + { + TSQuerySign *sign = (TSQuerySign *) palloc(sizeof(TSQuerySign)); + + retval = (GISTENTRY *) palloc(sizeof(GISTENTRY)); + *sign = makeTSQuerySign(DatumGetTSQuery(entry->key)); + + gistentryinit(*retval, PointerGetDatum(sign), + entry->rel, entry->page, + entry->offset, FALSE); + } + + PG_RETURN_POINTER(retval); +} + +Datum +gtsquery_decompress(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +Datum +gtsquery_consistent(PG_FUNCTION_ARGS) +{ + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); + TSQuerySign *key = (TSQuerySign *) DatumGetPointer(entry->key); + TSQuery query = PG_GETARG_TSQUERY(1); + StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2); + TSQuerySign sq = makeTSQuerySign(query); + bool retval; + + switch (strategy) + { + case RTContainsStrategyNumber: + if (GIST_LEAF(entry)) + retval = (*key & sq) == sq; + else + retval = (*key & sq) != 0; + break; + case RTContainedByStrategyNumber: + if (GIST_LEAF(entry)) + retval = (*key & sq) == *key; + else + retval = (*key & sq) != 0; + break; + default: + retval = FALSE; + } + PG_RETURN_BOOL(retval); +} + +Datum +gtsquery_union(PG_FUNCTION_ARGS) +{ + GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0); + int *size = (int *) PG_GETARG_POINTER(1); + TSQuerySign *sign = (TSQuerySign *) palloc(sizeof(TSQuerySign)); + int i; + + memset(sign, 0, sizeof(TSQuerySign)); + + for (i = 0; i < entryvec->n; i++) + *sign |= *GETENTRY(entryvec, i); + + *size = sizeof(TSQuerySign); + + PG_RETURN_POINTER(sign); +} + +Datum +gtsquery_same(PG_FUNCTION_ARGS) +{ + TSQuerySign *a = (TSQuerySign *) PG_GETARG_POINTER(0); + TSQuerySign *b = (TSQuerySign *) PG_GETARG_POINTER(1); + + PG_RETURN_POINTER(*a == *b); +} + +static int +sizebitvec(TSQuerySign sign) +{ + int size = 0, + i; + + for (i = 0; i < TSQS_SIGLEN; i++) + size += 0x01 & (sign >> i); + + return size; +} + +static int +hemdist(TSQuerySign a, TSQuerySign b) +{ + TSQuerySign res = a ^ b; + + return sizebitvec(res); +} + +Datum +gtsquery_penalty(PG_FUNCTION_ARGS) +{ + TSQuerySign *origval = (TSQuerySign *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(0))->key); + TSQuerySign *newval = (TSQuerySign *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(1))->key); + float *penalty = (float *) PG_GETARG_POINTER(2); + + *penalty = hemdist(*origval, *newval); + + PG_RETURN_POINTER(penalty); +} + + +typedef struct +{ + OffsetNumber pos; + int4 cost; +} SPLITCOST; + +static int +comparecost(const void *a, const void *b) +{ + if (((SPLITCOST *) a)->cost == ((SPLITCOST *) b)->cost) + return 0; + else + return (((SPLITCOST *) a)->cost > ((SPLITCOST *) b)->cost) ? 1 : -1; +} + +#define WISH_F(a,b,c) (double)( -(double)(((a)-(b))*((a)-(b))*((a)-(b)))*(c) ) + +Datum +gtsquery_picksplit(PG_FUNCTION_ARGS) +{ + GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0); + GIST_SPLITVEC *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1); + OffsetNumber maxoff = entryvec->n - 2; + OffsetNumber k, + j; + + TSQuerySign *datum_l, + *datum_r; + int4 size_alpha, + size_beta; + int4 size_waste, + waste = -1; + int4 nbytes; + OffsetNumber seed_1 = 0, + seed_2 = 0; + OffsetNumber *left, + *right; + + SPLITCOST *costvector; + + nbytes = (maxoff + 2) * sizeof(OffsetNumber); + left = v->spl_left = (OffsetNumber *) palloc(nbytes); + right = v->spl_right = (OffsetNumber *) palloc(nbytes); + v->spl_nleft = v->spl_nright = 0; + + for (k = FirstOffsetNumber; k < maxoff; k = OffsetNumberNext(k)) + for (j = OffsetNumberNext(k); j <= maxoff; j = OffsetNumberNext(j)) + { + size_waste = hemdist(*GETENTRY(entryvec, j), *GETENTRY(entryvec, k)); + if (size_waste > waste) + { + waste = size_waste; + seed_1 = k; + seed_2 = j; + } + } + + + if (seed_1 == 0 || seed_2 == 0) + { + seed_1 = 1; + seed_2 = 2; + } + + datum_l = (TSQuerySign *) palloc(sizeof(TSQuerySign)); + *datum_l = *GETENTRY(entryvec, seed_1); + datum_r = (TSQuerySign *) palloc(sizeof(TSQuerySign)); + *datum_r = *GETENTRY(entryvec, seed_2); + + + maxoff = OffsetNumberNext(maxoff); + costvector = (SPLITCOST *) palloc(sizeof(SPLITCOST) * maxoff); + for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j)) + { + costvector[j - 1].pos = j; + size_alpha = hemdist(*GETENTRY(entryvec, seed_1), *GETENTRY(entryvec, j)); + size_beta = hemdist(*GETENTRY(entryvec, seed_2), *GETENTRY(entryvec, j)); + costvector[j - 1].cost = abs(size_alpha - size_beta); + } + qsort((void *) costvector, maxoff, sizeof(SPLITCOST), comparecost); + + for (k = 0; k < maxoff; k++) + { + j = costvector[k].pos; + if (j == seed_1) + { + *left++ = j; + v->spl_nleft++; + continue; + } + else if (j == seed_2) + { + *right++ = j; + v->spl_nright++; + continue; + } + size_alpha = hemdist(*datum_l, *GETENTRY(entryvec, j)); + size_beta = hemdist(*datum_r, *GETENTRY(entryvec, j)); + + if (size_alpha < size_beta + WISH_F(v->spl_nleft, v->spl_nright, 0.05)) + { + *datum_l |= *GETENTRY(entryvec, j); + *left++ = j; + v->spl_nleft++; + } + else + { + *datum_r |= *GETENTRY(entryvec, j); + *right++ = j; + v->spl_nright++; + } + } + + *right = *left = FirstOffsetNumber; + v->spl_ldatum = PointerGetDatum(datum_l); + v->spl_rdatum = PointerGetDatum(datum_r); + + PG_RETURN_POINTER(v); +} |