设置约束无效的程序块

declare
  cursor curs is
    select 'alter table "' || owner || '"."' || table_name ||
           '" disable constraint "' || constraint_name || '"' text
      from sys.all_constraints
     where owner = 'CLAS'
       and constraint_type = 'R'
       and owner = r_owner;
  c_row       curs%rowtype;
  cursor_name INTEGER;
begin
  for c_row in curs loop
    cursor_name := DBMS_SQL.OPEN_CURSOR;
    DBMS_SQL.PARSE(cursor_name, c_row.text, DBMS_SQL.native);
    DBMS_SQL.CLOSE_CURSOR(cursor_name);
  end loop;
end;