[DO NOT MERGE] sp_xml_preparedocument

contrib/babelfishpg_tsql/sql/sys_procedures.sql

@@ -333,3 +333,38 @@ GRANT EXECUTE on PROCEDURE sys.sp_enum_oledb_providers() TO PUBLIC;
 CREATE OR REPLACE PROCEDURE sys.sp_reset_connection()
 AS 'babelfishpg_tsql', 'sp_reset_connection_internal' LANGUAGE C;
 GRANT EXECUTE ON PROCEDURE sys.sp_reset_connection() TO PUBLIC;
+
+CREATE OR REPLACE PROCEDURE sys.sp_xml_preparedocument(
+    INOUT hdoc INTEGER,                 
+    IN xmltext VARCHAR(8000) DEFAULT NULL,    
+    IN xpath_namespaces VARCHAR(8000) DEFAULT NULL 
+) 
+AS $$
+DECLARE
+    xml_data XML; 
+    ns_data XML;  
+BEGIN
+    CREATE TEMPORARY TABLE IF NOT EXISTS SessionXMLDocuments (
+        Handle INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,  
+        Xml_content XML,              
+        NamespaceDefinitions XML      
+    ) ON COMMIT PRESERVE ROWS;
+
+    IF xmltext IS NULL OR length(xmltext)=0 OR xml_is_well_formed_document(xmltext) THEN
+        xml_data := xmltext::XML; 
+    ELSE
+        RAISE EXCEPTION 'The XML input is not well-formed.';
+    END IF;
+
+    IF xpath_namespaces IS NULL OR length(xmltext)=0 OR xml_is_well_formed_document(xpath_namespaces) THEN
+        ns_data := xpath_namespaces::XML; 
+    ELSE
+        RAISE EXCEPTION 'The XPath namespace declarations are not well-formed.';
+    END IF;
+
+    INSERT INTO SessionXMLDocuments (Xml_content, NamespaceDefinitions)
+    VALUES (xml_data, ns_data)
+    RETURNING Handle INTO hdoc; 
+END;
+$$ 
+LANGUAGE plpgsql;