Optimizer cleanup.

src/backend/optimizer/util/restrictinfo.c

@@ -0,0 +1,190 @@
+/*-------------------------------------------------------------------------
+ *
+ * restrictinfo.c--
+ *	  RestrictInfo node manipulation routines.
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/util/restrictinfo.c,v 1.1 1999/02/05 19:59:31 momjian Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "nodes/relation.h"
+#include "nodes/nodeFuncs.h"
+
+#include "optimizer/internal.h"
+#include "optimizer/clauses.h"
+#include "optimizer/restrictinfo.h"
+
+/*
+ * valid-or-clause--
+ *
+ * Returns t iff the restrictinfo node contains a 'normal' 'or' clause.
+ *
+ */
+bool
+valid_or_clause(RestrictInfo * restrictinfo)
+{
+	if (restrictinfo != NULL &&
+		!single_node((Node *) restrictinfo->clause) &&
+		!restrictinfo->notclause &&
+		or_clause((Node *) restrictinfo->clause))
+		return true;
+	else
+		return false;
+}
+
+/*
+ * get-actual-clauses--
+ *
+ * Returns a list containing the clauses from 'restrictinfo-list'.
+ *
+ */
+List *
+get_actual_clauses(List *restrictinfo_list)
+{
+	List	   *temp = NIL;
+	List	   *result = NIL;
+	RestrictInfo *clause = (RestrictInfo *) NULL;
+
+	foreach(temp, restrictinfo_list)
+	{
+		clause = (RestrictInfo *) lfirst(temp);
+		result = lappend(result, clause->clause);
+	}
+	return result;
+}
+
+/*
+ * XXX NOTE:
+ *		The following routines must return their contents in the same order
+ *		(e.g., the first clause's info should be first, and so on) or else
+ *		get_index_sel() won't work.
+ *
+ */
+
+/*
+ * get_relattvals--
+ *	  For each member of  a list of restrictinfo nodes to be used with an
+ *	  index, create a vectori-long specifying:
+ *				the attnos,
+ *				the values of the clause constants, and
+ *				flags indicating the type and location of the constant within
+ *						each clause.
+ *	  Each clause is of the form (op var some_type_of_constant), thus the
+ *	  flag indicating whether the constant is on the left or right should
+ *	  always be *SELEC-CONSTANT-RIGHT*.
+ *
+ * 'restrictinfo-list' is a list of restrictinfo nodes
+ *
+ * Returns a list of vectori-longs.
+ *
+ */
+void
+get_relattvals(List *restrictinfo_list,
+			   List **attnos,
+			   List **values,
+			   List **flags)
+{
+	List	   *result1 = NIL;
+	List	   *result2 = NIL;
+	List	   *result3 = NIL;
+	RestrictInfo *temp = (RestrictInfo *) NULL;
+	List	   *i = NIL;
+
+	foreach(i, restrictinfo_list)
+	{
+		int			dummy;
+		AttrNumber	attno;
+		Datum		constval;
+		int			flag;
+
+		temp = (RestrictInfo *) lfirst(i);
+		get_relattval((Node *) temp->clause, &dummy, &attno, &constval, &flag);
+		result1 = lappendi(result1, (int) attno);
+		result2 = lappendi(result2, constval);
+		result3 = lappendi(result3, flag);
+	}
+
+	*attnos = result1;
+	*values = result2;
+	*flags = result3;
+	return;
+}
+
+/*
+ * get_joinvars --
+ *	  Given a list of join restrictinfo nodes to be used with the index
+ *	  of an inner join relation, return three lists consisting of:
+ *				the attributes corresponding to the inner join relation
+ *				the value of the inner var clause (always "")
+ *				whether the attribute appears on the left or right side of
+ *						the operator.
+ *
+ * 'relid' is the inner join relation
+ * 'restrictinfo-list' is a list of qualification clauses to be used with
+ *		'rel'
+ *
+ */
+void
+get_joinvars(Oid relid,
+			 List *restrictinfo_list,
+			 List **attnos,
+			 List **values,
+			 List **flags)
+{
+	List	   *result1 = NIL;
+	List	   *result2 = NIL;
+	List	   *result3 = NIL;
+	List	   *temp;
+
+	foreach(temp, restrictinfo_list)
+	{
+		RestrictInfo *restrictinfo = lfirst(temp);
+		Expr	   *clause = restrictinfo->clause;
+
+		if (IsA(get_leftop(clause), Var) &&
+			(relid == (get_leftop(clause))->varno))
+		{
+			result1 = lappendi(result1, (int4) (get_leftop(clause))->varattno);
+			result2 = lappend(result2, "");
+			result3 = lappendi(result3, _SELEC_CONSTANT_RIGHT_);
+		}
+		else
+		{
+			result1 = lappendi(result1, (int4) (get_rightop(clause))->varattno);
+			result2 = lappend(result2, "");
+			result3 = lappendi(result3, _SELEC_CONSTANT_LEFT_);
+		}
+	}
+	*attnos = result1;
+	*values = result2;
+	*flags = result3;
+	return;
+}
+
+/*
+ * get_opnos--
+ *	  Create and return a list containing the clause operators of each member
+ *	  of a list of restrictinfo nodes to be used with an index.
+ *
+ */
+List *
+get_opnos(List *restrictinfo_list)
+{
+	RestrictInfo *temp = (RestrictInfo *) NULL;
+	List	   *result = NIL;
+	List	   *i = NIL;
+
+	foreach(i, restrictinfo_list)
+	{
+		temp = (RestrictInfo *) lfirst(i);
+		result = lappendi(result,
+					 (((Oper *) temp->clause->oper)->opno));
+	}
+	return result;
+}