oracle批量化查询表名注释

DECLARE
  v_sqls  varchar2(5000) := '';
  type projects_varray2 is varray(64) of varchar2(200); --定义数组
  --手动输入表名
  v_projects projects_varray2:=projects_varray2('table_name_test1',
'table_name_test2',
'table_name_test3',
'table_name_test4'
);
begin
--循环获得表名称
  for x in v_projects.first .. v_projects.last loop
  --查询标注释赋值给v_sqls
      select comments INTO v_sqls from user_tab_comments a where a.TABLE_NAME=v_projects(x);
      IF v_sqls IS NULL  THEN v_sqls:='无注释'; 
      END IF;
      dbms_output.put_line(v_projects(x)||'注释为:' ||v_sqls|| ';');  
  end loop;
end;