weixin_43927116的博客

–查询死锁select * from vlockedobjecta,dbaobjectsaa,vlocked_object a ,dba_objects aa,vlockedo​bjecta,dbao​bjectsaa,vsession b where a.session_id = b.sid and a.OBJECT_ID=aa.OBJECT_ID order by b.logon_time;–杀掉死锁alter system kill session ‘47,60033’;–SID,SERIAL#

select sys_guid() from dual connect by rownum<128

– 表结构复制create table test_a as SELECT * FROM test

update test_aset test_a.aaaa =(SELECT b.bbbbbb FROM test_b where ttest_a.id=test_b.aId)

SELECT@s := @s + 1 AS index,DATE( DATE_SUB( DATE_FORMAT(‘2019-11-10’,’%Y-%m-%d’), INTERVAL @s DAY ) ) AS dateFROMmysql.help_topic,( SELECT @s := - 1 ) tempWHERE@s < 10ORDER BYdate DESC函数天DAY 周WEEK 月MONTH

天之间的时间差SELECT TIMESTAMPDIFF(DAY,‘2019-12-29’,‘2020-01-08’)周之间的时间差SELECT TIMESTAMPDIFF(WEEK,‘2019-12-29’,‘2020-01-08’)月之间的时间差SELECT TIMESTAMPDIFF(MONTH,#{startTime}, DATE_FORMAT(#{endTime}, ‘%Y-%m-%d’))...