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HomeDatabaseMysql Tutorialmysql如何处理varchar与nvarchar类型中的特殊字符_MySQL

如果你每次建数据表的时候固执的使用varchar,那么你可能会遇到以下的问题:

现在saleUserName的字段类型为varchar(50)

update TableNameset saleUserName='小覃祝你⑭快乐' where ID=87

select * from TableName where ID=87

why?SaleUserName字段里的文字怎么变成这样了。⑭这个符号怎么变成了?

好的,那么我现在将saleUserName的字段类型改为nvarchar(50)呢

updateTableNameset saleUserName='小覃祝你⑭快乐' where ID=87

select * from TableName where ID=87

What!?怎么还是一样!

那么,稍微改一下,在参数值前面加上N。现在可以看到调皮的⑭出来了。

updateTableNameset saleUserName=N'小覃祝你⑭快乐' where ID=87

------加上N代表存入数据库时以Unicode格式存储。

----------------------------------------------------------总结的时候,我总是得召唤出这么华丽的分割线-----------------------------------------------------------------

unicode,以前学习的时候看过,根本没留心。那么好,百度一下,百度百科是这么说的:Unicode是国际组织制定的可以容纳世界上所有文字和符号的字符编码方案。

nvarchar和ntext就是可以容纳unicode的类型,所以才能存储调皮的⑭等特殊字符。

以前根本没留意过这些数据类型,看到说是存unicode类型的,可是根本不知道unicode为何物。码农就是这么任性,不够重视这些东西。

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