SQL收集

24、mysql 更新语句、新增列、删除列

update user set name='张三' where id=111
# 删除
DELETE FROM table_name [WHERE Clause]

# 增加字段
alter table 表名 add column 列名 类型;
# 删除字段
alter table 表名 dropcolumn 列名 ;

sql 查询

# 联合更新
update malluser set master_master_id=3 where master_id in (select a.id from (select id from  malluser where id like '15%')a)
# 统计某字段重复数据
SELECT phone, COUNT(*) AS sumCount FROM malluser GROUP BY phone HAVING sumCount > 1;