SQL语句修改表操作

前言

此博客用于记录工作用到的SQL语句，持续更新，欢迎补充！

清空表中某一列的所有值

UPDATE table_name SET column_name = null

注：table_name 为表名 column_name为字段名

批量给指定列插入数据（python中拼接代码）

sql = "UPDATE  TM_AP SET APID_2='%s' WHERE APAD in ('%s','%s') " % (max_APID,APADlist[i],APADlist[i+1])

查询（指定列）有重复数据的行

select  *  from  table_name  where  column_name  in ( select  column_name  from  table_name  group  by  column_name  having  COUNT (*)>1)

删除（指定列）不重复的数据行

DELETE FROM table_name WHERE column_name  in ( select  column_name  from  table_name  group  by  column_name having  COUNT (*)=1)

新增列

alter table 表名 add 列名 数据类型;
# 案例
ALTER TABLE table_name ADD column_name INT;