大家一定遇到过要为MySQL数据库中的某个表中的某个字段连接一个特定的字符串，很容易想到的方法是
update 表名 set 字段名 = ‘字符串’+字段名;此方法在Sql server 2008 r2可用，在Sql server 2008 r2中要将查询结果的两个字段连接可用如下语句
select 字段名1+字段名2 from 表名;
但是这种方式会报错，1292 Truncated incorrect DOUBLE value: '
没有找到这种方式为什么会报这种错误，但可以找个替代方式
update 表名 set 字段名 =concat(‘字符串’,字段名);
能达到同样效果，若有朋友知道为什么，告诉我答案。谢谢
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