LENGTH函数返回文本字段中值的长度。

SQL LENGTH() 语法
SELECT LENGTH(column_name) FROM table_name

select * from broker_info where LENGTH(avatar)=11

更新

update `broker_info` set cityid=2 WHERE LENGTH(avatar)=11

字段之间更新

update `broker_info` set `mobile`=`avatar` WHERE LENGTH(avatar)=11