Update RESTORE behaviour for LIKE operator for CS_AI collation (#3207)

(cherry picked from commit 3fe245b)

contrib/babelfishpg_common/src/collation.c

@@ -1326,6 +1326,24 @@ has_ilike_node(Node *expr)
 	return false;
 }
 
+bool
+has_like_node(Node *expr)
+{
+	OpExpr	   *op;
+
+	Assert(IsA(expr, OpExpr));
+
+	op = (OpExpr *) expr;
+	for (int i = 0; i < TOTAL_LIKE_OP_COUNT; i++)
+	{
+		if (strcmp(get_opname(op->opno), like_ilike_table[i].like_op_name) == 0)
+		{
+			return true;
+		}
+	}
+	return false;
+}
+
 Datum
 is_collated_ci_as_internal(PG_FUNCTION_ARGS)
 {
@@ -1625,6 +1643,7 @@ get_collation_callbacks(void)
 		collation_callbacks_var.find_cs_as_collation_internal = &find_cs_as_collation;
 		collation_callbacks_var.find_collation_internal = &find_collation;
 		collation_callbacks_var.has_ilike_node = &has_ilike_node;
+		collation_callbacks_var.has_like_node = &has_like_node;
 		collation_callbacks_var.translate_bbf_collation_to_tsql_collation = &translate_bbf_collation_to_tsql_collation;
 		collation_callbacks_var.translate_tsql_collation_to_bbf_collation = &translate_tsql_collation_to_bbf_collation;
 		collation_callbacks_var.set_db_collation = &set_db_collation;

contrib/babelfishpg_common/src/collation.h

@@ -113,6 +113,8 @@ typedef struct collation_callbacks
 
 	bool		(*has_ilike_node) (Node *expr);
 
+	bool		(*has_like_node) (Node *expr);
+
 	const char *(*translate_bbf_collation_to_tsql_collation) (const char *collname);
 
 	const char *(*translate_tsql_collation_to_bbf_collation) (const char *collname);
@@ -147,6 +149,7 @@ extern const char *translate_bbf_collation_to_tsql_collation(const char *collnam
 extern const char *translate_tsql_collation_to_bbf_collation(const char *collname);
 Oid			get_oid_from_collidx(int collidx);
 extern bool has_ilike_node(Node *expr);
+extern bool has_like_node(Node *expr);
 extern Oid	babelfish_define_type_default_collation(Oid typeNamespace);
 extern void	set_db_collation(Oid db_coll);
 

contrib/babelfishpg_tsql/src/collation.c

@@ -942,9 +942,14 @@ transform_likenode(Node *node)
 		 * by a user. So, it is safe to go ahead with replacing the ci_as
 		 * collation with a corresponding cs_as one if an ILIKE node is found
 		 * during dump and restore.
+		 * For CS_AI collation, we keep the LIKE operator but convert it to
+		 * CS_AS by adding a call to remove_accents_internal*. During restore,
+		 * it will take the same code path and will try to add a new call to
+		 * remove_accents_internal* on top of current node. So, we take care
+		 * of that case here.
 		 */
 		init_and_check_collation_callbacks();
-		if ((*collation_callbacks_ptr->has_ilike_node) (node) && babelfish_dump_restore)
+		if (babelfish_dump_restore && ((*collation_callbacks_ptr->has_ilike_node) (node) || (*collation_callbacks_ptr->has_like_node) (node)))
 		{
 			int			collidx_of_cs_as;
 
@@ -965,6 +970,13 @@ transform_likenode(Node *node)
 				/* If a collation is not specified, use the default one */
 				op->inputcollid = DEFAULT_COLLATION_OID;
 			}
+
+			/*
+			 * If this has a like node, then it is CS collation
+			 * So we can return from here directly
+			 */
+			if ((*collation_callbacks_ptr->has_like_node) (node))
+				return node;
 		}
 
 		if (OidIsValid(like_entry.like_oid) &&

contrib/babelfishpg_tsql/src/collation.h

@@ -82,6 +82,8 @@ typedef struct collation_callbacks
 
 	bool		(*has_ilike_node) (Node *expr);
 
+	bool		(*has_like_node) (Node *expr);
+
 	const char *(*translate_bbf_collation_to_tsql_collation) (const char *collname);
 
 	const char *(*translate_tsql_collation_to_bbf_collation) (const char *collname);