如何从数据库列中爆炸用户ID? [英] How to explode user id from a database column?

问题描述

我有一个表名消息.有一个列名receiver_id，我需要在 receiver_id = 4 的地方获取记录，但是我总是得到空输出.

I have a table name messages. There is a column name receiver_id I need to fetch record where receiver_id = 4 but i am always getting null output.

请参阅我的表格屏幕截图-

See my table Screenshot-

上面的屏幕快照有3行.第二行和第三行与其他ID一起存在4，我需要将其爆炸并显示第二行和第三行记录.

Above screenshot there are 3rows. second and third rows exist 4 along with other ids i need to explode that and show the second and third record.

如何编写MySQL查询?

How to write MySQL query?

推荐答案

存储逗号分隔的值确实是一个错误的设计，您应该 normalize ，首先将所有接收方关联存储在联结表中，如果您无法更改架构，则可以针对当前情况使用

Storing comma separated values is really a bad design you should normalize it first by storing all association of receiver in a junction table,If you are not able to alter your schema then for your current situation you can use find_in_set() to search values in a comma separated list

select * from table 
where find_in_set(4,receiver_id ) >0

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