1 files changed, 135 insertions, 0 deletions
diff --git a/src/backend/nodes/makefuncs.c b/src/backend/nodes/makefuncs.c
index 079d0160a8b..7085ed2c4c8 100644
--- a/src/backend/nodes/makefuncs.c
+++ b/src/backend/nodes/makefuncs.c
@@ -599,6 +599,141 @@ makeFuncCall(List *name, List *args, int location)
 }
 
 /*
+ * make_opclause
+ *	  Creates an operator clause given its operator info, left operand
+ *	  and right operand (pass NULL to create single-operand clause),
+ *	  and collation info.
+ */
+Expr *
+make_opclause(Oid opno, Oid opresulttype, bool opretset,
+			  Expr *leftop, Expr *rightop,
+			  Oid opcollid, Oid inputcollid)
+{
+	OpExpr	   *expr = makeNode(OpExpr);
+
+	expr->opno = opno;
+	expr->opfuncid = InvalidOid;
+	expr->opresulttype = opresulttype;
+	expr->opretset = opretset;
+	expr->opcollid = opcollid;
+	expr->inputcollid = inputcollid;
+	if (rightop)
+		expr->args = list_make2(leftop, rightop);
+	else
+		expr->args = list_make1(leftop);
+	expr->location = -1;
+	return (Expr *) expr;
+}
+
+/*
+ * make_andclause
+ *
+ * Creates an 'and' clause given a list of its subclauses.
+ */
+Expr *
+make_andclause(List *andclauses)
+{
+	BoolExpr   *expr = makeNode(BoolExpr);
+
+	expr->boolop = AND_EXPR;
+	expr->args = andclauses;
+	expr->location = -1;
+	return (Expr *) expr;
+}
+
+/*
+ * make_orclause
+ *
+ * Creates an 'or' clause given a list of its subclauses.
+ */
+Expr *
+make_orclause(List *orclauses)
+{
+	BoolExpr   *expr = makeNode(BoolExpr);
+
+	expr->boolop = OR_EXPR;
+	expr->args = orclauses;
+	expr->location = -1;
+	return (Expr *) expr;
+}
+
+/*
+ * make_notclause
+ *
+ * Create a 'not' clause given the expression to be negated.
+ */
+Expr *
+make_notclause(Expr *notclause)
+{
+	BoolExpr   *expr = makeNode(BoolExpr);
+
+	expr->boolop = NOT_EXPR;
+	expr->args = list_make1(notclause);
+	expr->location = -1;
+	return (Expr *) expr;
+}
+
+/*
+ * make_and_qual
+ *
+ * Variant of make_andclause for ANDing two qual conditions together.
+ * Qual conditions have the property that a NULL nodetree is interpreted
+ * as 'true'.
+ *
+ * NB: this makes no attempt to preserve AND/OR flatness; so it should not
+ * be used on a qual that has already been run through prepqual.c.
+ */
+Node *
+make_and_qual(Node *qual1, Node *qual2)
+{
+	if (qual1 == NULL)
+		return qual2;
+	if (qual2 == NULL)
+		return qual1;
+	return (Node *) make_andclause(list_make2(qual1, qual2));
+}
+
+/*
+ * The planner and executor usually represent qualification expressions
+ * as lists of boolean expressions with implicit AND semantics.
+ *
+ * These functions convert between an AND-semantics expression list and the
+ * ordinary representation of a boolean expression.
+ *
+ * Note that an empty list is considered equivalent to TRUE.
+ */
+Expr *
+make_ands_explicit(List *andclauses)
+{
+	if (andclauses == NIL)
+		return (Expr *) makeBoolConst(true, false);
+	else if (list_length(andclauses) == 1)
+		return (Expr *) linitial(andclauses);
+	else
+		return make_andclause(andclauses);
+}
+
+List *
+make_ands_implicit(Expr *clause)
+{
+	/*
+	 * NB: because the parser sets the qual field to NULL in a query that has
+	 * no WHERE clause, we must consider a NULL input clause as TRUE, even
+	 * though one might more reasonably think it FALSE.
+	 */
+	if (clause == NULL)
+		return NIL;				/* NULL -> NIL list == TRUE */
+	else if (is_andclause(clause))
+		return ((BoolExpr *) clause)->args;
+	else if (IsA(clause, Const) &&
+			 !((Const *) clause)->constisnull &&
+			 DatumGetBool(((Const *) clause)->constvalue))
+		return NIL;				/* constant TRUE input -> NIL list */
+	else
+		return list_make1(clause);
+}
+
+/*
  * makeGroupingSet
  *
  */