記錄學習中用到的sql語句

1、根據一張表更新另一張表的資料

update t_table t1

set a = t2.a,
b = t2.b
from t_table t2
where t1.name=t2.name

mybatis批量更新

update mydata_table

when id=# then #
where id in
#

update mydata_table 

set status = 
case
when id = # then #//此處應該是展開值
endwhere id in (...);

select extract(epoch from now())

select * from b where (select count(1) from a where a.id = b.id) = 0

滲透中用到的sql語句 mysql篇

找到含有密碼欄位的表 select table name,column name from information schema.columns where column name like pwd or column name like passw 找含有特定內容的表名 select table ...

mysql中用到的一些sql語句

檢視資料庫預設配置資訊 show variables 檢視mysql資料庫編碼方式 show variables like character set database 檢視資料庫裡表的編碼方式,同時還能看到該錶使用的儲存引擎資訊 show create table char test 修改資料庫編...

不常用到的sql語句記錄

1 查詢觸發器是否存在 oracle select count as count from user triggers where trigger name upper triname sqlserver select count as count from sysobjects where nam...