如何使用闪回查询来获取已删除的行?

时间:2017-03-08 14:15:19

标签: oracle flashback

我正在尝试测试从表中删除数据的存储过程,并设置类似于此的设置:

Oracle安装程序

CREATE TABLE table_name ( id NUMBER );

PL / SQL脚本

DECLARE
  v_scn V$DATABASE.CURRENT_SCN%TYPE;
  v_row TABLE_NAME%ROWTYPE;
BEGIN
  INSERT INTO table_name VALUES ( 1 );
  INSERT INTO table_name VALUES ( 2 );
  INSERT INTO table_name VALUES ( 3 );

  SELECT current_scn INTO v_scn FROM V$DATABASE;

  -- call a procedure with side-effects such as:
  DELETE FROM table_name WHERE id = 1;

  SELECT *
  INTO   v_row
  FROM   (
    SELECT * FROM table_name AS OF SCN( v_scn )
  MINUS
    SELECT * FROM table_name
  );

  DBMS_OUTPUT.PUT_LINE( 'One row deleted: ' || v_row.id );
EXCEPTION
  WHEN NO_DATA_FOUND THEN
    DBMS_OUTPUT.PUT_LINE( 'Not found' );
  WHEN TOO_MANY_ROWS THEN
    DBMS_OUTPUT.PUT_LINE( 'Too many rows' );
END;

ROLLBACK;

我希望v_row将填充一行,并且不会调用任何异常处理程序。但是,正在调用NO_DATA_FOUND异常。

  • 为什么不起作用?
  • 如何使用闪回查询来确定哪些行已被删除?

0 个答案:

没有答案