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Diffstat (limited to 'contrib/ltree/_ltree_gist.c')
| -rw-r--r-- | contrib/ltree/_ltree_gist.c | 558 |
1 files changed, 558 insertions, 0 deletions
diff --git a/contrib/ltree/_ltree_gist.c b/contrib/ltree/_ltree_gist.c new file mode 100644 index 0000000..e89a39a --- /dev/null +++ b/contrib/ltree/_ltree_gist.c @@ -0,0 +1,558 @@ +/* + * contrib/ltree/_ltree_gist.c + * + * + * GiST support for ltree[] + * Teodor Sigaev <teodor@stack.net> + */ +#include "postgres.h" + +#include <math.h> + +#include "access/gist.h" +#include "access/reloptions.h" +#include "access/stratnum.h" +#include "crc32.h" +#include "ltree.h" +#include "port/pg_bitutils.h" +#include "utils/array.h" + +PG_FUNCTION_INFO_V1(_ltree_compress); +PG_FUNCTION_INFO_V1(_ltree_same); +PG_FUNCTION_INFO_V1(_ltree_union); +PG_FUNCTION_INFO_V1(_ltree_penalty); +PG_FUNCTION_INFO_V1(_ltree_picksplit); +PG_FUNCTION_INFO_V1(_ltree_consistent); +PG_FUNCTION_INFO_V1(_ltree_gist_options); + +#define GETENTRY(vec,pos) ((ltree_gist *) DatumGetPointer((vec)->vector[(pos)].key)) +#define NEXTVAL(x) ( (ltree*)( (char*)(x) + INTALIGN( VARSIZE(x) ) ) ) + +#define WISH_F(a,b,c) (double)( -(double)(((a)-(b))*((a)-(b))*((a)-(b)))*(c) ) + + +static void +hashing(BITVECP sign, ltree *t, int siglen) +{ + int tlen = t->numlevel; + ltree_level *cur = LTREE_FIRST(t); + int hash; + + while (tlen > 0) + { + hash = ltree_crc32_sz(cur->name, cur->len); + AHASH(sign, hash, siglen); + cur = LEVEL_NEXT(cur); + tlen--; + } +} + +Datum +_ltree_compress(PG_FUNCTION_ARGS) +{ + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); + GISTENTRY *retval = entry; + int siglen = LTREE_GET_ASIGLEN(); + + if (entry->leafkey) + { /* ltree */ + ltree_gist *key; + ArrayType *val = DatumGetArrayTypeP(entry->key); + int num = ArrayGetNItems(ARR_NDIM(val), ARR_DIMS(val)); + ltree *item = (ltree *) ARR_DATA_PTR(val); + + if (ARR_NDIM(val) > 1) + ereport(ERROR, + (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), + errmsg("array must be one-dimensional"))); + if (array_contains_nulls(val)) + ereport(ERROR, + (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), + errmsg("array must not contain nulls"))); + + key = ltree_gist_alloc(false, NULL, siglen, NULL, NULL); + + while (num > 0) + { + hashing(LTG_SIGN(key), item, siglen); + num--; + item = NEXTVAL(item); + } + + retval = (GISTENTRY *) palloc(sizeof(GISTENTRY)); + gistentryinit(*retval, PointerGetDatum(key), + entry->rel, entry->page, + entry->offset, false); + } + else if (!LTG_ISALLTRUE(entry->key)) + { + int32 i; + ltree_gist *key; + BITVECP sign = LTG_SIGN(DatumGetPointer(entry->key)); + + ALOOPBYTE(siglen) + { + if ((sign[i] & 0xff) != 0xff) + PG_RETURN_POINTER(retval); + } + + key = ltree_gist_alloc(true, sign, siglen, NULL, NULL); + retval = (GISTENTRY *) palloc(sizeof(GISTENTRY)); + gistentryinit(*retval, PointerGetDatum(key), + entry->rel, entry->page, + entry->offset, false); + } + PG_RETURN_POINTER(retval); +} + +Datum +_ltree_same(PG_FUNCTION_ARGS) +{ + ltree_gist *a = (ltree_gist *) PG_GETARG_POINTER(0); + ltree_gist *b = (ltree_gist *) PG_GETARG_POINTER(1); + bool *result = (bool *) PG_GETARG_POINTER(2); + int siglen = LTREE_GET_ASIGLEN(); + + if (LTG_ISALLTRUE(a) && LTG_ISALLTRUE(b)) + *result = true; + else if (LTG_ISALLTRUE(a)) + *result = false; + else if (LTG_ISALLTRUE(b)) + *result = false; + else + { + int32 i; + BITVECP sa = LTG_SIGN(a), + sb = LTG_SIGN(b); + + *result = true; + ALOOPBYTE(siglen) + { + if (sa[i] != sb[i]) + { + *result = false; + break; + } + } + } + PG_RETURN_POINTER(result); +} + +static int32 +unionkey(BITVECP sbase, ltree_gist *add, int siglen) +{ + int32 i; + BITVECP sadd = LTG_SIGN(add); + + if (LTG_ISALLTRUE(add)) + return 1; + + ALOOPBYTE(siglen) + sbase[i] |= sadd[i]; + return 0; +} + +Datum +_ltree_union(PG_FUNCTION_ARGS) +{ + GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0); + int *size = (int *) PG_GETARG_POINTER(1); + int siglen = LTREE_GET_ASIGLEN(); + int32 i; + ltree_gist *result = ltree_gist_alloc(false, NULL, siglen, NULL, NULL); + BITVECP base = LTG_SIGN(result); + + for (i = 0; i < entryvec->n; i++) + { + if (unionkey(base, GETENTRY(entryvec, i), siglen)) + { + result->flag |= LTG_ALLTRUE; + SET_VARSIZE(result, LTG_HDRSIZE); + break; + } + } + + *size = VARSIZE(result); + + PG_RETURN_POINTER(result); +} + +static int32 +sizebitvec(BITVECP sign, int siglen) +{ + return pg_popcount((const char *) sign, siglen); +} + +static int +hemdistsign(BITVECP a, BITVECP b, int siglen) +{ + int i, + diff, + dist = 0; + + ALOOPBYTE(siglen) + { + diff = (unsigned char) (a[i] ^ b[i]); + /* Using the popcount functions here isn't likely to win */ + dist += pg_number_of_ones[diff]; + } + return dist; +} + +static int +hemdist(ltree_gist *a, ltree_gist *b, int siglen) +{ + if (LTG_ISALLTRUE(a)) + { + if (LTG_ISALLTRUE(b)) + return 0; + else + return ASIGLENBIT(siglen) - sizebitvec(LTG_SIGN(b), siglen); + } + else if (LTG_ISALLTRUE(b)) + return ASIGLENBIT(siglen) - sizebitvec(LTG_SIGN(a), siglen); + + return hemdistsign(LTG_SIGN(a), LTG_SIGN(b), siglen); +} + + +Datum +_ltree_penalty(PG_FUNCTION_ARGS) +{ + ltree_gist *origval = (ltree_gist *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(0))->key); + ltree_gist *newval = (ltree_gist *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(1))->key); + float *penalty = (float *) PG_GETARG_POINTER(2); + int siglen = LTREE_GET_ASIGLEN(); + + *penalty = hemdist(origval, newval, siglen); + PG_RETURN_POINTER(penalty); +} + +typedef struct +{ + OffsetNumber pos; + int32 cost; +} SPLITCOST; + +static int +comparecost(const void *a, const void *b) +{ + return ((const SPLITCOST *) a)->cost - ((const SPLITCOST *) b)->cost; +} + +Datum +_ltree_picksplit(PG_FUNCTION_ARGS) +{ + GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0); + GIST_SPLITVEC *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1); + int siglen = LTREE_GET_ASIGLEN(); + OffsetNumber k, + j; + ltree_gist *datum_l, + *datum_r; + BITVECP union_l, + union_r; + int32 size_alpha, + size_beta; + int32 size_waste, + waste = -1; + int32 nbytes; + OffsetNumber seed_1 = 0, + seed_2 = 0; + OffsetNumber *left, + *right; + OffsetNumber maxoff; + BITVECP ptr; + int i; + SPLITCOST *costvector; + ltree_gist *_k, + *_j; + + maxoff = entryvec->n - 2; + nbytes = (maxoff + 2) * sizeof(OffsetNumber); + v->spl_left = (OffsetNumber *) palloc(nbytes); + v->spl_right = (OffsetNumber *) palloc(nbytes); + + for (k = FirstOffsetNumber; k < maxoff; k = OffsetNumberNext(k)) + { + _k = GETENTRY(entryvec, k); + for (j = OffsetNumberNext(k); j <= maxoff; j = OffsetNumberNext(j)) + { + size_waste = hemdist(_k, GETENTRY(entryvec, j), siglen); + if (size_waste > waste) + { + waste = size_waste; + seed_1 = k; + seed_2 = j; + } + } + } + + left = v->spl_left; + v->spl_nleft = 0; + right = v->spl_right; + v->spl_nright = 0; + + if (seed_1 == 0 || seed_2 == 0) + { + seed_1 = 1; + seed_2 = 2; + } + + /* form initial .. */ + datum_l = ltree_gist_alloc(LTG_ISALLTRUE(GETENTRY(entryvec, seed_1)), + LTG_SIGN(GETENTRY(entryvec, seed_1)), + siglen, NULL, NULL); + + datum_r = ltree_gist_alloc(LTG_ISALLTRUE(GETENTRY(entryvec, seed_2)), + LTG_SIGN(GETENTRY(entryvec, seed_2)), + siglen, NULL, NULL); + + maxoff = OffsetNumberNext(maxoff); + /* sort before ... */ + costvector = (SPLITCOST *) palloc(sizeof(SPLITCOST) * maxoff); + for (j = FirstOffsetNumber; j <= maxoff; j = OffsetNumberNext(j)) + { + costvector[j - 1].pos = j; + _j = GETENTRY(entryvec, j); + size_alpha = hemdist(datum_l, _j, siglen); + size_beta = hemdist(datum_r, _j, siglen); + costvector[j - 1].cost = abs(size_alpha - size_beta); + } + qsort(costvector, maxoff, sizeof(SPLITCOST), comparecost); + + union_l = LTG_SIGN(datum_l); + union_r = LTG_SIGN(datum_r); + + 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; + } + _j = GETENTRY(entryvec, j); + size_alpha = hemdist(datum_l, _j, siglen); + size_beta = hemdist(datum_r, _j, siglen); + + if (size_alpha < size_beta + WISH_F(v->spl_nleft, v->spl_nright, 0.00001)) + { + if (LTG_ISALLTRUE(datum_l) || LTG_ISALLTRUE(_j)) + { + if (!LTG_ISALLTRUE(datum_l)) + memset(union_l, 0xff, siglen); + } + else + { + ptr = LTG_SIGN(_j); + ALOOPBYTE(siglen) + union_l[i] |= ptr[i]; + } + *left++ = j; + v->spl_nleft++; + } + else + { + if (LTG_ISALLTRUE(datum_r) || LTG_ISALLTRUE(_j)) + { + if (!LTG_ISALLTRUE(datum_r)) + memset(union_r, 0xff, siglen); + } + else + { + ptr = LTG_SIGN(_j); + ALOOPBYTE(siglen) + union_r[i] |= ptr[i]; + } + *right++ = j; + v->spl_nright++; + } + } + + *right = *left = FirstOffsetNumber; + + v->spl_ldatum = PointerGetDatum(datum_l); + v->spl_rdatum = PointerGetDatum(datum_r); + + PG_RETURN_POINTER(v); +} + +static bool +gist_te(ltree_gist *key, ltree *query, int siglen) +{ + ltree_level *curq = LTREE_FIRST(query); + BITVECP sign = LTG_SIGN(key); + int qlen = query->numlevel; + unsigned int hv; + + if (LTG_ISALLTRUE(key)) + return true; + + while (qlen > 0) + { + hv = ltree_crc32_sz(curq->name, curq->len); + if (!GETBIT(sign, AHASHVAL(hv, siglen))) + return false; + curq = LEVEL_NEXT(curq); + qlen--; + } + + return true; +} + +typedef struct LtreeSignature +{ + BITVECP sign; + int siglen; +} LtreeSignature; + +static bool +checkcondition_bit(void *cxt, ITEM *val) +{ + LtreeSignature *sig = cxt; + + return (FLG_CANLOOKSIGN(val->flag)) ? GETBIT(sig->sign, AHASHVAL(val->val, sig->siglen)) : true; +} + +static bool +gist_qtxt(ltree_gist *key, ltxtquery *query, int siglen) +{ + LtreeSignature sig; + + if (LTG_ISALLTRUE(key)) + return true; + + sig.sign = LTG_SIGN(key); + sig.siglen = siglen; + + return ltree_execute(GETQUERY(query), + &sig, false, + checkcondition_bit); +} + +static bool +gist_qe(ltree_gist *key, lquery *query, int siglen) +{ + lquery_level *curq = LQUERY_FIRST(query); + BITVECP sign = LTG_SIGN(key); + int qlen = query->numlevel; + + if (LTG_ISALLTRUE(key)) + return true; + + while (qlen > 0) + { + if (curq->numvar && LQL_CANLOOKSIGN(curq)) + { + bool isexist = false; + int vlen = curq->numvar; + lquery_variant *curv = LQL_FIRST(curq); + + while (vlen > 0) + { + if (GETBIT(sign, AHASHVAL(curv->val, siglen))) + { + isexist = true; + break; + } + curv = LVAR_NEXT(curv); + vlen--; + } + if (!isexist) + return false; + } + + curq = LQL_NEXT(curq); + qlen--; + } + + return true; +} + +static bool +_arrq_cons(ltree_gist *key, ArrayType *_query, int siglen) +{ + lquery *query = (lquery *) ARR_DATA_PTR(_query); + int num = ArrayGetNItems(ARR_NDIM(_query), ARR_DIMS(_query)); + + if (ARR_NDIM(_query) > 1) + ereport(ERROR, + (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR), + errmsg("array must be one-dimensional"))); + if (array_contains_nulls(_query)) + ereport(ERROR, + (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), + errmsg("array must not contain nulls"))); + + while (num > 0) + { + if (gist_qe(key, query, siglen)) + return true; + num--; + query = (lquery *) NEXTVAL(query); + } + return false; +} + +Datum +_ltree_consistent(PG_FUNCTION_ARGS) +{ + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); + void *query = (void *) PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); + StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2); + + /* Oid subtype = PG_GETARG_OID(3); */ + bool *recheck = (bool *) PG_GETARG_POINTER(4); + int siglen = LTREE_GET_ASIGLEN(); + ltree_gist *key = (ltree_gist *) DatumGetPointer(entry->key); + bool res = false; + + /* All cases served by this function are inexact */ + *recheck = true; + + switch (strategy) + { + case 10: + case 11: + res = gist_te(key, (ltree *) query, siglen); + break; + case 12: + case 13: + res = gist_qe(key, (lquery *) query, siglen); + break; + case 14: + case 15: + res = gist_qtxt(key, (ltxtquery *) query, siglen); + break; + case 16: + case 17: + res = _arrq_cons(key, (ArrayType *) query, siglen); + break; + default: + /* internal error */ + elog(ERROR, "unrecognized StrategyNumber: %d", strategy); + } + PG_FREE_IF_COPY(query, 1); + PG_RETURN_BOOL(res); +} + +Datum +_ltree_gist_options(PG_FUNCTION_ARGS) +{ + local_relopts *relopts = (local_relopts *) PG_GETARG_POINTER(0); + + init_local_reloptions(relopts, sizeof(LtreeGistOptions)); + add_local_int_reloption(relopts, "siglen", "signature length", + LTREE_ASIGLEN_DEFAULT, 1, LTREE_ASIGLEN_MAX, + offsetof(LtreeGistOptions, siglen)); + + PG_RETURN_VOID(); +} |