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diff --git a/src/backend/access/gist/giststrat.c b/src/backend/access/gist/giststrat.c
new file mode 100644
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+++ b/src/backend/access/gist/giststrat.c
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+/*-------------------------------------------------------------------------
+ *
+ * giststrat.c--
+ *    strategy map data for GiSTs.
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *    /usr/local/devel/pglite/cvs/src/backend/access/gist/giststrat.c,v 1.4 1995/06/14 00:10:05 jolly Exp
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "c.h"
+
+#include "utils/rel.h"
+
+#include "storage/bufmgr.h"
+#include "storage/bufpage.h"
+
+#include "access/istrat.h"
+#include "access/gist.h"
+
+/*
+ *  Note:  negate, commute, and negatecommute all assume that operators are
+ *	   ordered as follows in the strategy map:
+ *
+ *	contains, contained-by
+ *
+ *  The negate, commute, and negatecommute arrays are used by the planner
+ *  to plan indexed scans over data that appears in the qualificiation in
+ *  a boolean negation, or whose operands appear in the wrong order.  For
+ *  example, if the operator "<%" means "contains", and the user says
+ *
+ *	where not rel.box <% "(10,10,20,20)"::box
+ *
+ *  the planner can plan an index scan by noting that GiST indices have
+ *  an operator in their operator class for negating <%.
+ *
+ *  Similarly, if the user says something like
+ *
+ *	where "(10,10,20,20)"::box <% rel.box
+ *
+ *  the planner can see that the GiST index on rel.box has an operator in
+ *  its opclass for commuting <%, and plan the scan using that operator.
+ *  This added complexity in the access methods makes the planner a lot easier
+ *  to write.
+ */
+
+/* if a op b, what operator tells us if (not a op b)? */
+static StrategyNumber	GISTNegate[GISTNStrategies] = {
+    InvalidStrategy,
+    InvalidStrategy,
+    InvalidStrategy
+    };
+
+/* if a op_1 b, what is the operator op_2 such that b op_2 a? */
+static StrategyNumber	GISTCommute[GISTNStrategies] = {
+    InvalidStrategy,
+    InvalidStrategy,
+    InvalidStrategy
+    };
+
+/* if a op_1 b, what is the operator op_2 such that (b !op_2 a)? */
+static StrategyNumber	GISTNegateCommute[GISTNStrategies] = {
+    InvalidStrategy,
+    InvalidStrategy,
+    InvalidStrategy
+    };
+
+/*
+ * GiSTs do not currently support TermData (see rtree/rtstrat.c for 
+ * discussion of
+ * TermData) -- such logic must be encoded in the user's Consistent function.
+ */
+
+/*
+ *  If you were sufficiently attentive to detail, you would go through
+ *  the ExpressionData pain above for every one of the strategies
+ *  we defined.  I am not.  Now we declare the StrategyEvaluationData
+ *  structure that gets shipped around to help the planner and the access
+ *  method decide what sort of scan it should do, based on (a) what the
+ *  user asked for, (b) what operators are defined for a particular opclass,
+ *  and (c) the reams of information we supplied above.
+ *
+ *  The idea of all of this initialized data is to make life easier on the
+ *  user when he defines a new operator class to use this access method.
+ *  By filling in all the data, we let him get away with leaving holes in his
+ *  operator class, and still let him use the index.  The added complexity
+ *  in the access methods just isn't worth the trouble, though.
+ */
+
+static StrategyEvaluationData GISTEvaluationData = {
+    GISTNStrategies,				/* # of strategies */
+    (StrategyTransformMap) GISTNegate,	/* how to do (not qual) */
+    (StrategyTransformMap) GISTCommute,	/* how to swap operands */
+    (StrategyTransformMap) GISTNegateCommute,	/* how to do both */
+    NULL
+};
+
+StrategyNumber
+RelationGetGISTStrategy(Relation r,
+		      AttrNumber attnum,
+		      RegProcedure proc)
+{
+    return (RelationGetStrategy(r, attnum, &GISTEvaluationData, proc));
+}
+
+bool
+RelationInvokeGISTStrategy(Relation r,
+			 AttrNumber attnum,
+			 StrategyNumber s,
+			 Datum left,
+			 Datum right)
+{
+    return (RelationInvokeStrategy(r, &GISTEvaluationData, attnum, s,
+				   left, right));
+}
+