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mysql支持utf8mb4字符集,即已支持emoji表情符号的存储。
现在想用emoji作为where的一个条件进行select,是否有可能实现?怎么实现呢?


回复讨论(解决方案)

只要你能在编辑器中打出来,查询和其他字符没什么区别

我用chrome +phpmyadmin中用mysql搜:
select * from `table` where `nickname` like convert(_utf8 '%

郁闷,发个emoji居然被截了,改用论坛支持的emoji凑合吧。

我用chrome +phpmyadmin中用mysql搜:
select * from `table` where `nickname` like convert(_utf8 '%%' USING utf8mb4) COLLATE utf8mb4_general_ci
结果为空。但是可以肯定有一条记录的nickname内含有这个emoji。

我手边的设备都不支持 emoji,无法给出准确的表达式
但原理应该是这样的:
如果你的字段是 utf8mb4_general_ci 的,那么字段中的 emoji 就是以 4 字节的 utf-8 存在的
如果你能输入 emoji 到字符串,那么查询语句就是
select * from `table` where `nickname` like '%$txt%'

如果你想指定某个 emoji,而你又无法输入的话,可以用十六进制内码表示。比如
$ch = "\xf0\x9f\x98\x84";
$ch = "\xf0\x9f\x98\x83";

如果没有 emoji 对照表,那么写个小程序用支持 emoji 的设备探测一下就知道了

chrome装了个扩展可以输入emoji,对照表我也有。
我也试过用select * from `table` where `nickname` like '%\xf0%' ; 结果也是为空。这一点还是没想明白为啥。
比较奇怪的一点就是:phpmyadmin上看4字节的emoji是问号,3字节的能正常显示。而直接读库取出来echo的话是能正常显示的,证明mysql已经支持4字节的emoji了。那么看到问号只是因为phpmyadmin的缘故?

phpmyadmin上看4字节的emoji是问号这是正常的
虽然你的字段是 utf8mb4 但 phpmaiadmin 是 utf-8 的,编码转不过来自然就是问号了

你  nickname like '%\xf0%' 是不行的,因为文本方式下是按字查找的 \xf0 不会单独存在
要声明 nickname 是二进制的才行
BINARY nickname like '%\xf0%'
 

select * from `table` where BINARY `nickname` like '%\xf0%' ;
也为空哦。。。

select * from `table` where BINARY `nickname` like '%整个emoji%' ;
这样就可以了,感谢老xu的热心帮忙

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