summaryrefslogtreecommitdiffstats
path: root/contrib/intarray/_int_gist.c
diff options
context:
space:
mode:
Diffstat (limited to 'contrib/intarray/_int_gist.c')
-rw-r--r--contrib/intarray/_int_gist.c624
1 files changed, 624 insertions, 0 deletions
diff --git a/contrib/intarray/_int_gist.c b/contrib/intarray/_int_gist.c
new file mode 100644
index 0000000..fb05b06
--- /dev/null
+++ b/contrib/intarray/_int_gist.c
@@ -0,0 +1,624 @@
+/*
+ * contrib/intarray/_int_gist.c
+ */
+#include "postgres.h"
+
+#include <limits.h>
+
+#include "_int.h"
+#include "access/gist.h"
+#include "access/reloptions.h"
+#include "access/stratnum.h"
+
+#define GETENTRY(vec,pos) ((ArrayType *) DatumGetPointer((vec)->vector[(pos)].key))
+
+/*
+ * Control the maximum sparseness of compressed keys.
+ *
+ * The upper safe bound for this limit is half the maximum allocatable array
+ * size. A lower bound would give more guarantees that pathological data
+ * wouldn't eat excessive CPU and memory, but at the expense of breaking
+ * possibly working (after a fashion) indexes.
+ */
+#define MAXNUMELTS (Min((MaxAllocSize / sizeof(Datum)),((MaxAllocSize - ARR_OVERHEAD_NONULLS(1)) / sizeof(int)))/2)
+/* or: #define MAXNUMELTS 1000000 */
+
+/*
+** GiST support methods
+*/
+PG_FUNCTION_INFO_V1(g_int_consistent);
+PG_FUNCTION_INFO_V1(g_int_compress);
+PG_FUNCTION_INFO_V1(g_int_decompress);
+PG_FUNCTION_INFO_V1(g_int_penalty);
+PG_FUNCTION_INFO_V1(g_int_picksplit);
+PG_FUNCTION_INFO_V1(g_int_union);
+PG_FUNCTION_INFO_V1(g_int_same);
+PG_FUNCTION_INFO_V1(g_int_options);
+
+
+/*
+** The GiST Consistent method for _intments
+** Should return false if for all data items x below entry,
+** the predicate x op query == false, where op is the oper
+** corresponding to strategy in the pg_amop table.
+*/
+Datum
+g_int_consistent(PG_FUNCTION_ARGS)
+{
+ GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
+ ArrayType *query = PG_GETARG_ARRAYTYPE_P_COPY(1);
+ StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
+
+ /* Oid subtype = PG_GETARG_OID(3); */
+ bool *recheck = (bool *) PG_GETARG_POINTER(4);
+ bool retval;
+
+ /* this is exact except for RTSameStrategyNumber */
+ *recheck = (strategy == RTSameStrategyNumber);
+
+ if (strategy == BooleanSearchStrategy)
+ {
+ retval = execconsistent((QUERYTYPE *) query,
+ (ArrayType *) DatumGetPointer(entry->key),
+ GIST_LEAF(entry));
+
+ pfree(query);
+ PG_RETURN_BOOL(retval);
+ }
+
+ /* sort query for fast search, key is already sorted */
+ CHECKARRVALID(query);
+ PREPAREARR(query);
+
+ switch (strategy)
+ {
+ case RTOverlapStrategyNumber:
+ retval = inner_int_overlap((ArrayType *) DatumGetPointer(entry->key),
+ query);
+ break;
+ case RTSameStrategyNumber:
+ if (GIST_LEAF(entry))
+ DirectFunctionCall3(g_int_same,
+ entry->key,
+ PointerGetDatum(query),
+ PointerGetDatum(&retval));
+ else
+ retval = inner_int_contains((ArrayType *) DatumGetPointer(entry->key),
+ query);
+ break;
+ case RTContainsStrategyNumber:
+ case RTOldContainsStrategyNumber:
+ retval = inner_int_contains((ArrayType *) DatumGetPointer(entry->key),
+ query);
+ break;
+ case RTContainedByStrategyNumber:
+ case RTOldContainedByStrategyNumber:
+ if (GIST_LEAF(entry))
+ retval = inner_int_contains(query,
+ (ArrayType *) DatumGetPointer(entry->key));
+ else
+ {
+ /*
+ * Unfortunately, because empty arrays could be anywhere in
+ * the index, we must search the whole tree.
+ */
+ retval = true;
+ }
+ break;
+ default:
+ retval = false;
+ }
+ pfree(query);
+ PG_RETURN_BOOL(retval);
+}
+
+Datum
+g_int_union(PG_FUNCTION_ARGS)
+{
+ GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
+ int *size = (int *) PG_GETARG_POINTER(1);
+ int32 i,
+ *ptr;
+ ArrayType *res;
+ int totlen = 0;
+
+ for (i = 0; i < entryvec->n; i++)
+ {
+ ArrayType *ent = GETENTRY(entryvec, i);
+
+ CHECKARRVALID(ent);
+ totlen += ARRNELEMS(ent);
+ }
+
+ res = new_intArrayType(totlen);
+ ptr = ARRPTR(res);
+
+ for (i = 0; i < entryvec->n; i++)
+ {
+ ArrayType *ent = GETENTRY(entryvec, i);
+ int nel;
+
+ nel = ARRNELEMS(ent);
+ memcpy(ptr, ARRPTR(ent), nel * sizeof(int32));
+ ptr += nel;
+ }
+
+ QSORT(res, 1);
+ res = _int_unique(res);
+ *size = VARSIZE(res);
+ PG_RETURN_POINTER(res);
+}
+
+/*
+** GiST Compress and Decompress methods
+*/
+Datum
+g_int_compress(PG_FUNCTION_ARGS)
+{
+ GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
+ GISTENTRY *retval;
+ ArrayType *r;
+ int num_ranges = G_INT_GET_NUMRANGES();
+ int len,
+ lenr;
+ int *dr;
+ int i,
+ j,
+ cand;
+ int64 min;
+
+ if (entry->leafkey)
+ {
+ r = DatumGetArrayTypePCopy(entry->key);
+ CHECKARRVALID(r);
+ PREPAREARR(r);
+
+ if (ARRNELEMS(r) >= 2 * num_ranges)
+ elog(NOTICE, "input array is too big (%d maximum allowed, %d current), use gist__intbig_ops opclass instead",
+ 2 * num_ranges - 1, ARRNELEMS(r));
+
+ retval = palloc(sizeof(GISTENTRY));
+ gistentryinit(*retval, PointerGetDatum(r),
+ entry->rel, entry->page, entry->offset, false);
+
+ PG_RETURN_POINTER(retval);
+ }
+
+ /*
+ * leaf entries never compress one more time, only when entry->leafkey
+ * ==true, so now we work only with internal keys
+ */
+
+ r = DatumGetArrayTypeP(entry->key);
+ CHECKARRVALID(r);
+ if (ARRISEMPTY(r))
+ {
+ if (r != (ArrayType *) DatumGetPointer(entry->key))
+ pfree(r);
+ PG_RETURN_POINTER(entry);
+ }
+
+ if ((len = ARRNELEMS(r)) >= 2 * num_ranges)
+ { /* compress */
+ if (r == (ArrayType *) DatumGetPointer(entry->key))
+ r = DatumGetArrayTypePCopy(entry->key);
+ r = resize_intArrayType(r, 2 * (len));
+
+ dr = ARRPTR(r);
+
+ /*
+ * "len" at this point is the number of ranges we will construct.
+ * "lenr" is the number of ranges we must eventually remove by
+ * merging, we must be careful to remove no more than this number.
+ */
+ lenr = len - num_ranges;
+
+ /*
+ * Initially assume we can merge consecutive ints into a range. but we
+ * must count every value removed and stop when lenr runs out
+ */
+ for (j = i = len - 1; i > 0 && lenr > 0; i--, j--)
+ {
+ int r_end = dr[i];
+ int r_start = r_end;
+
+ while (i > 0 && lenr > 0 && dr[i - 1] == r_start - 1)
+ --r_start, --i, --lenr;
+ dr[2 * j] = r_start;
+ dr[2 * j + 1] = r_end;
+ }
+ /* just copy the rest, if any, as trivial ranges */
+ for (; i >= 0; i--, j--)
+ dr[2 * j] = dr[2 * j + 1] = dr[i];
+
+ if (++j)
+ {
+ /*
+ * shunt everything down to start at the right place
+ */
+ memmove((void *) &dr[0], (void *) &dr[2 * j], 2 * (len - j) * sizeof(int32));
+ }
+
+ /*
+ * make "len" be number of array elements, not ranges
+ */
+ len = 2 * (len - j);
+ cand = 1;
+ while (len > num_ranges * 2)
+ {
+ min = PG_INT64_MAX;
+ for (i = 2; i < len; i += 2)
+ if (min > ((int64) dr[i] - (int64) dr[i - 1]))
+ {
+ min = ((int64) dr[i] - (int64) dr[i - 1]);
+ cand = i;
+ }
+ memmove((void *) &dr[cand - 1], (void *) &dr[cand + 1], (len - cand - 1) * sizeof(int32));
+ len -= 2;
+ }
+
+ /*
+ * check sparseness of result
+ */
+ lenr = internal_size(dr, len);
+ if (lenr < 0 || lenr > MAXNUMELTS)
+ ereport(ERROR,
+ (errmsg("data is too sparse, recreate index using gist__intbig_ops opclass instead")));
+
+ r = resize_intArrayType(r, len);
+ retval = palloc(sizeof(GISTENTRY));
+ gistentryinit(*retval, PointerGetDatum(r),
+ entry->rel, entry->page, entry->offset, false);
+ PG_RETURN_POINTER(retval);
+ }
+ else
+ PG_RETURN_POINTER(entry);
+}
+
+Datum
+g_int_decompress(PG_FUNCTION_ARGS)
+{
+ GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
+ GISTENTRY *retval;
+ ArrayType *r;
+ int num_ranges = G_INT_GET_NUMRANGES();
+ int *dr,
+ lenr;
+ ArrayType *in;
+ int lenin;
+ int *din;
+ int i,
+ j;
+
+ in = DatumGetArrayTypeP(entry->key);
+
+ CHECKARRVALID(in);
+ if (ARRISEMPTY(in))
+ {
+ if (in != (ArrayType *) DatumGetPointer(entry->key))
+ {
+ retval = palloc(sizeof(GISTENTRY));
+ gistentryinit(*retval, PointerGetDatum(in),
+ entry->rel, entry->page, entry->offset, false);
+ PG_RETURN_POINTER(retval);
+ }
+
+ PG_RETURN_POINTER(entry);
+ }
+
+ lenin = ARRNELEMS(in);
+
+ if (lenin < 2 * num_ranges)
+ { /* not compressed value */
+ if (in != (ArrayType *) DatumGetPointer(entry->key))
+ {
+ retval = palloc(sizeof(GISTENTRY));
+ gistentryinit(*retval, PointerGetDatum(in),
+ entry->rel, entry->page, entry->offset, false);
+
+ PG_RETURN_POINTER(retval);
+ }
+ PG_RETURN_POINTER(entry);
+ }
+
+ din = ARRPTR(in);
+ lenr = internal_size(din, lenin);
+ if (lenr < 0 || lenr > MAXNUMELTS)
+ ereport(ERROR,
+ (errmsg("compressed array is too big, recreate index using gist__intbig_ops opclass instead")));
+
+ r = new_intArrayType(lenr);
+ dr = ARRPTR(r);
+
+ for (i = 0; i < lenin; i += 2)
+ for (j = din[i]; j <= din[i + 1]; j++)
+ if ((!i) || *(dr - 1) != j)
+ *dr++ = j;
+
+ if (in != (ArrayType *) DatumGetPointer(entry->key))
+ pfree(in);
+ retval = palloc(sizeof(GISTENTRY));
+ gistentryinit(*retval, PointerGetDatum(r),
+ entry->rel, entry->page, entry->offset, false);
+
+ PG_RETURN_POINTER(retval);
+}
+
+/*
+** The GiST Penalty method for _intments
+*/
+Datum
+g_int_penalty(PG_FUNCTION_ARGS)
+{
+ GISTENTRY *origentry = (GISTENTRY *) PG_GETARG_POINTER(0);
+ GISTENTRY *newentry = (GISTENTRY *) PG_GETARG_POINTER(1);
+ float *result = (float *) PG_GETARG_POINTER(2);
+ ArrayType *ud;
+ float tmp1,
+ tmp2;
+
+ ud = inner_int_union((ArrayType *) DatumGetPointer(origentry->key),
+ (ArrayType *) DatumGetPointer(newentry->key));
+ rt__int_size(ud, &tmp1);
+ rt__int_size((ArrayType *) DatumGetPointer(origentry->key), &tmp2);
+ *result = tmp1 - tmp2;
+ pfree(ud);
+
+ PG_RETURN_POINTER(result);
+}
+
+
+
+Datum
+g_int_same(PG_FUNCTION_ARGS)
+{
+ ArrayType *a = PG_GETARG_ARRAYTYPE_P(0);
+ ArrayType *b = PG_GETARG_ARRAYTYPE_P(1);
+ bool *result = (bool *) PG_GETARG_POINTER(2);
+ int32 n = ARRNELEMS(a);
+ int32 *da,
+ *db;
+
+ CHECKARRVALID(a);
+ CHECKARRVALID(b);
+
+ if (n != ARRNELEMS(b))
+ {
+ *result = false;
+ PG_RETURN_POINTER(result);
+ }
+ *result = true;
+ da = ARRPTR(a);
+ db = ARRPTR(b);
+ while (n--)
+ {
+ if (*da++ != *db++)
+ {
+ *result = false;
+ break;
+ }
+ }
+
+ PG_RETURN_POINTER(result);
+}
+
+/*****************************************************************
+** Common GiST Method
+*****************************************************************/
+
+typedef struct
+{
+ OffsetNumber pos;
+ float cost;
+} SPLITCOST;
+
+static int
+comparecost(const void *a, const void *b)
+{
+ if (((const SPLITCOST *) a)->cost == ((const SPLITCOST *) b)->cost)
+ return 0;
+ else
+ return (((const SPLITCOST *) a)->cost > ((const SPLITCOST *) b)->cost) ? 1 : -1;
+}
+
+/*
+** The GiST PickSplit method for _intments
+** We use Guttman's poly time split algorithm
+*/
+Datum
+g_int_picksplit(PG_FUNCTION_ARGS)
+{
+ GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
+ GIST_SPLITVEC *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1);
+ OffsetNumber i,
+ j;
+ ArrayType *datum_alpha,
+ *datum_beta;
+ ArrayType *datum_l,
+ *datum_r;
+ ArrayType *union_d,
+ *union_dl,
+ *union_dr;
+ ArrayType *inter_d;
+ bool firsttime;
+ float size_alpha,
+ size_beta,
+ size_union,
+ size_inter;
+ float size_waste,
+ waste;
+ float size_l,
+ size_r;
+ int nbytes;
+ OffsetNumber seed_1 = 0,
+ seed_2 = 0;
+ OffsetNumber *left,
+ *right;
+ OffsetNumber maxoff;
+ SPLITCOST *costvector;
+
+#ifdef GIST_DEBUG
+ elog(DEBUG3, "--------picksplit %d", entryvec->n);
+#endif
+
+ maxoff = entryvec->n - 2;
+ nbytes = (maxoff + 2) * sizeof(OffsetNumber);
+ v->spl_left = (OffsetNumber *) palloc(nbytes);
+ v->spl_right = (OffsetNumber *) palloc(nbytes);
+
+ firsttime = true;
+ waste = 0.0;
+ for (i = FirstOffsetNumber; i < maxoff; i = OffsetNumberNext(i))
+ {
+ datum_alpha = GETENTRY(entryvec, i);
+ for (j = OffsetNumberNext(i); j <= maxoff; j = OffsetNumberNext(j))
+ {
+ datum_beta = GETENTRY(entryvec, j);
+
+ /* compute the wasted space by unioning these guys */
+ /* size_waste = size_union - size_inter; */
+ union_d = inner_int_union(datum_alpha, datum_beta);
+ rt__int_size(union_d, &size_union);
+ inter_d = inner_int_inter(datum_alpha, datum_beta);
+ rt__int_size(inter_d, &size_inter);
+ size_waste = size_union - size_inter;
+
+ pfree(union_d);
+ pfree(inter_d);
+
+ /*
+ * are these a more promising split that what we've already seen?
+ */
+
+ if (size_waste > waste || firsttime)
+ {
+ waste = size_waste;
+ seed_1 = i;
+ seed_2 = j;
+ firsttime = false;
+ }
+ }
+ }
+
+ 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;
+ }
+
+ datum_alpha = GETENTRY(entryvec, seed_1);
+ datum_l = copy_intArrayType(datum_alpha);
+ rt__int_size(datum_l, &size_l);
+ datum_beta = GETENTRY(entryvec, seed_2);
+ datum_r = copy_intArrayType(datum_beta);
+ rt__int_size(datum_r, &size_r);
+
+ maxoff = OffsetNumberNext(maxoff);
+
+ /*
+ * sort entries
+ */
+ costvector = (SPLITCOST *) palloc(sizeof(SPLITCOST) * maxoff);
+ for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
+ {
+ costvector[i - 1].pos = i;
+ datum_alpha = GETENTRY(entryvec, i);
+ union_d = inner_int_union(datum_l, datum_alpha);
+ rt__int_size(union_d, &size_alpha);
+ pfree(union_d);
+ union_d = inner_int_union(datum_r, datum_alpha);
+ rt__int_size(union_d, &size_beta);
+ pfree(union_d);
+ costvector[i - 1].cost = Abs((size_alpha - size_l) - (size_beta - size_r));
+ }
+ qsort((void *) costvector, maxoff, sizeof(SPLITCOST), comparecost);
+
+ /*
+ * Now split up the regions between the two seeds. An important property
+ * of this split algorithm is that the split vector v has the indices of
+ * items to be split in order in its left and right vectors. We exploit
+ * this property by doing a merge in the code that actually splits the
+ * page.
+ *
+ * For efficiency, we also place the new index tuple in this loop. This is
+ * handled at the very end, when we have placed all the existing tuples
+ * and i == maxoff + 1.
+ */
+
+
+ for (j = 0; j < maxoff; j++)
+ {
+ i = costvector[j].pos;
+
+ /*
+ * If we've already decided where to place this item, just put it on
+ * the right list. Otherwise, we need to figure out which page needs
+ * the least enlargement in order to store the item.
+ */
+
+ if (i == seed_1)
+ {
+ *left++ = i;
+ v->spl_nleft++;
+ continue;
+ }
+ else if (i == seed_2)
+ {
+ *right++ = i;
+ v->spl_nright++;
+ continue;
+ }
+
+ /* okay, which page needs least enlargement? */
+ datum_alpha = GETENTRY(entryvec, i);
+ union_dl = inner_int_union(datum_l, datum_alpha);
+ union_dr = inner_int_union(datum_r, datum_alpha);
+ rt__int_size(union_dl, &size_alpha);
+ rt__int_size(union_dr, &size_beta);
+
+ /* pick which page to add it to */
+ if (size_alpha - size_l < size_beta - size_r + WISH_F(v->spl_nleft, v->spl_nright, 0.01))
+ {
+ pfree(datum_l);
+ pfree(union_dr);
+ datum_l = union_dl;
+ size_l = size_alpha;
+ *left++ = i;
+ v->spl_nleft++;
+ }
+ else
+ {
+ pfree(datum_r);
+ pfree(union_dl);
+ datum_r = union_dr;
+ size_r = size_beta;
+ *right++ = i;
+ v->spl_nright++;
+ }
+ }
+ pfree(costvector);
+ *right = *left = FirstOffsetNumber;
+
+ v->spl_ldatum = PointerGetDatum(datum_l);
+ v->spl_rdatum = PointerGetDatum(datum_r);
+
+ PG_RETURN_POINTER(v);
+}
+
+Datum
+g_int_options(PG_FUNCTION_ARGS)
+{
+ local_relopts *relopts = (local_relopts *) PG_GETARG_POINTER(0);
+
+ init_local_reloptions(relopts, sizeof(GISTIntArrayOptions));
+ add_local_int_reloption(relopts, "numranges",
+ "number of ranges for compression",
+ G_INT_NUMRANGES_DEFAULT, 1, G_INT_NUMRANGES_MAX,
+ offsetof(GISTIntArrayOptions, num_ranges));
+
+ PG_RETURN_VOID();
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-13 10:15:40 +0000