RUM index access methods with Postgresql 9.3 GIN

Author: Artur Zakirov

Makefile

@@ -0,0 +1,21 @@
+# contrib/rum/Makefile
+
+MODULE_big = rum
+OBJS = rumutil.o ruminsert.o $(WIN32RES)
+
+EXTENSION = rum
+DATA = rum--1.0.sql
+PGFILEDESC = "RUM access method"
+
+REGRESS = rum
+
+ifdef USE_PGXS
+PG_CONFIG = pg_config
+PGXS := $(shell $(PG_CONFIG) --pgxs)
+include $(PGXS)
+else
+subdir = contrib/rum
+top_builddir = ../..
+include $(top_builddir)/src/Makefile.global
+include $(top_srcdir)/contrib/contrib-global.mk
+endif

ginarrayproc.c

@@ -0,0 +1,220 @@
+/*-------------------------------------------------------------------------
+ *
+ * ginarrayproc.c
+ *	  support functions for GIN's indexing of any array
+ *
+ *
+ * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ *	  src/backend/access/gin/ginarrayproc.c
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "access/gin.h"
+#include "access/skey.h"
+#include "utils/array.h"
+#include "utils/builtins.h"
+#include "utils/lsyscache.h"
+
+
+#define GinOverlapStrategy		1
+#define GinContainsStrategy		2
+#define GinContainedStrategy	3
+#define GinEqualStrategy		4
+
+
+/*
+ * extractValue support function
+ */
+Datum
+ginarrayextract(PG_FUNCTION_ARGS)
+{
+	/* Make copy of array input to ensure it doesn't disappear while in use */
+	ArrayType  *array = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	int32	   *nkeys = (int32 *) PG_GETARG_POINTER(1);
+	bool	  **nullFlags = (bool **) PG_GETARG_POINTER(2);
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	Datum	   *elems;
+	bool	   *nulls;
+	int			nelems;
+
+	get_typlenbyvalalign(ARR_ELEMTYPE(array),
+						 &elmlen, &elmbyval, &elmalign);
+
+	deconstruct_array(array,
+					  ARR_ELEMTYPE(array),
+					  elmlen, elmbyval, elmalign,
+					  &elems, &nulls, &nelems);
+
+	*nkeys = nelems;
+	*nullFlags = nulls;
+
+	/* we should not free array, elems[i] points into it */
+	PG_RETURN_POINTER(elems);
+}
+
+/*
+ * Formerly, ginarrayextract had only two arguments.  Now it has three,
+ * but we still need a pg_proc entry with two args to support reloading
+ * pre-9.1 contrib/intarray opclass declarations.  This compatibility
+ * function should go away eventually.
+ */
+Datum
+ginarrayextract_2args(PG_FUNCTION_ARGS)
+{
+	if (PG_NARGS() < 3)			/* should not happen */
+		elog(ERROR, "ginarrayextract requires three arguments");
+	return ginarrayextract(fcinfo);
+}
+
+/*
+ * extractQuery support function
+ */
+Datum
+ginqueryarrayextract(PG_FUNCTION_ARGS)
+{
+	/* Make copy of array input to ensure it doesn't disappear while in use */
+	ArrayType  *array = PG_GETARG_ARRAYTYPE_P_COPY(0);
+	int32	   *nkeys = (int32 *) PG_GETARG_POINTER(1);
+	StrategyNumber strategy = PG_GETARG_UINT16(2);
+
+	/* bool   **pmatch = (bool **) PG_GETARG_POINTER(3); */
+	/* Pointer	   *extra_data = (Pointer *) PG_GETARG_POINTER(4); */
+	bool	  **nullFlags = (bool **) PG_GETARG_POINTER(5);
+	int32	   *searchMode = (int32 *) PG_GETARG_POINTER(6);
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	Datum	   *elems;
+	bool	   *nulls;
+	int			nelems;
+
+	get_typlenbyvalalign(ARR_ELEMTYPE(array),
+						 &elmlen, &elmbyval, &elmalign);
+
+	deconstruct_array(array,
+					  ARR_ELEMTYPE(array),
+					  elmlen, elmbyval, elmalign,
+					  &elems, &nulls, &nelems);
+
+	*nkeys = nelems;
+	*nullFlags = nulls;
+
+	switch (strategy)
+	{
+		case GinOverlapStrategy:
+			*searchMode = GIN_SEARCH_MODE_DEFAULT;
+			break;
+		case GinContainsStrategy:
+			if (nelems > 0)
+				*searchMode = GIN_SEARCH_MODE_DEFAULT;
+			else	/* everything contains the empty set */
+				*searchMode = GIN_SEARCH_MODE_ALL;
+			break;
+		case GinContainedStrategy:
+			/* empty set is contained in everything */
+			*searchMode = GIN_SEARCH_MODE_INCLUDE_EMPTY;
+			break;
+		case GinEqualStrategy:
+			if (nelems > 0)
+				*searchMode = GIN_SEARCH_MODE_DEFAULT;
+			else
+				*searchMode = GIN_SEARCH_MODE_INCLUDE_EMPTY;
+			break;
+		default:
+			elog(ERROR, "ginqueryarrayextract: unknown strategy number: %d",
+				 strategy);
+	}
+
+	/* we should not free array, elems[i] points into it */
+	PG_RETURN_POINTER(elems);
+}
+
+/*
+ * consistent support function
+ */
+Datum
+ginarrayconsistent(PG_FUNCTION_ARGS)
+{
+	bool	   *check = (bool *) PG_GETARG_POINTER(0);
+	StrategyNumber strategy = PG_GETARG_UINT16(1);
+
+	/* ArrayType  *query = PG_GETARG_ARRAYTYPE_P(2); */
+	int32		nkeys = PG_GETARG_INT32(3);
+
+	/* Pointer	   *extra_data = (Pointer *) PG_GETARG_POINTER(4); */
+	bool	   *recheck = (bool *) PG_GETARG_POINTER(5);
+
+	/* Datum	   *queryKeys = (Datum *) PG_GETARG_POINTER(6); */
+	bool	   *nullFlags = (bool *) PG_GETARG_POINTER(7);
+	bool		res;
+	int32		i;
+
+	switch (strategy)
+	{
+		case GinOverlapStrategy:
+			/* result is not lossy */
+			*recheck = false;
+			/* must have a match for at least one non-null element */
+			res = false;
+			for (i = 0; i < nkeys; i++)
+			{
+				if (check[i] && !nullFlags[i])
+				{
+					res = true;
+					break;
+				}
+			}
+			break;
+		case GinContainsStrategy:
+			/* result is not lossy */
+			*recheck = false;
+			/* must have all elements in check[] true, and no nulls */
+			res = true;
+			for (i = 0; i < nkeys; i++)
+			{
+				if (!check[i] || nullFlags[i])
+				{
+					res = false;
+					break;
+				}
+			}
+			break;
+		case GinContainedStrategy:
+			/* we will need recheck */
+			*recheck = true;
+			/* can't do anything else useful here */
+			res = true;
+			break;
+		case GinEqualStrategy:
+			/* we will need recheck */
+			*recheck = true;
+
+			/*
+			 * Must have all elements in check[] true; no discrimination
+			 * against nulls here.  This is because array_contain_compare and
+			 * array_eq handle nulls differently ...
+			 */
+			res = true;
+			for (i = 0; i < nkeys; i++)
+			{
+				if (!check[i])
+				{
+					res = false;
+					break;
+				}
+			}
+			break;
+		default:
+			elog(ERROR, "ginarrayconsistent: unknown strategy number: %d",
+				 strategy);
+			res = false;
+	}
+
+	PG_RETURN_BOOL(res);
+}