mysql列的值默认不区分大小写

现象：

SELECT * FROM econtract_signature WHERE contract_id='mj201707191900111744_14'SELECT * FROM econtract_signature WHERE contract_id='MJ201707191900111744_14'

这两个语句查出的数据是一样的。

解决办法是：

可以在查询条件前加BINARY

例如上面的可以改成

SELECT * FROM econtract_signature WHERE BINARY  contract_id='mj201707191900111744_14'SELECT * FROM econtract_signature WHERE BINARY  contract_id='MJ201707191900111744_14'

或者多条件查询时：

SELECT * FROM econtract_signature WHERE BINARY  contract_id='MJ201707191900111744_14' AND BINARY original_group_name = 'Group1'

每个条件都要加上 BINARY关键字