我使用此处显示的存储过程通过参数化表名、提交计数和where条件来删除12个大型表。我已经将这3条信息插入到一个名为 PURGE_DEL
它有12行,我想要一些建议,如何通过一个接一个地从表中读取来自动删除12个表。
像这样的
表名:purge\ U del
CALL DELETE_DATA(PURGE_DEL.TABLE_NAME, PURGE_DEL.COMMIT_COUNT, PURGE_DEL.WHERE)
代码:
CREATE PROCEDURE DELETE_DATA
(IN V_TABLE_NAME VARCHAR(24),
IN V_COMMIT_COUNT INTEGER,
IN V_WHERE_CONDITION VARCHAR(1024))
DYNAMIC RESULT SETS 01
COMMIT ON RETURN NO
LANGUAGE SQL
NOT DETERMINISTIC
L3 : BEGIN
-- DECLARE STATEMENTS
DECLARE SQLCODE INTEGER;
DECLARE V_DELETE_QUERY VARCHAR(1024);
DECLARE V_DELETE_STATEMENT STATEMENT;
SET V_DELETE_QUERY = 'DELETE FROM ' || V_TABLE_NAME ||
' WHERE COLUMN IN (SELECT COLUMN FROM '
|| V_TABLE_NAME || 'WHERE COLUMN_ID ='
|| V_WHERE_CONDITION || ' FETCH FIRST '
|| RTRIM(CHAR(V_COMMIT_COUNT)) || ' ROWS ONLY) ';
PREPARE V_DELETE_STATEMENT FROM V_DELETE_QUERY;
DEL_LOOP:
LOOP
EXECUTE V_DELETE_STATEMENT;
IF SQLCODE = 100 THEN
LEAVE DEL_LOOP;
END IF;
COMMIT;
END LOOP;
COMMIT;
END L3
还请建议对存储过程进行任何更改。
1条答案
按热度按时间inkz8wg91#
出于兴趣,您可以使用这种类型的delete来避免delete中代价高昂的自连接
而且,如果您确实希望高效地清除行,可以考虑使用mdc卷展栏删除
https://www.ibm.com/support/knowledgecenter/ssepgg_11.5.0/com.ibm.db2.luw.admin.perf.doc/doc/c0007338.html