mysql - 如何在sql语句中判断一个字段(内容为文件的路径)里面的文件后缀名？求大神告知，不会啊

Answer 1

MYSQL:

SELECT RIGHT(RTRIM(@Path), LOCATE('.',REVERSE(RTRIM(@Path))) - 1)

SQLSERVER:

SELECT RIGHT(RTRIM(@Path), CHARINDEX('.',REVERSE(RTRIM(@Path))) - 1)

Assume the @Path placeholder is your field. Idea: To find the last character ., reverse it and find the position of the first ., and then go to the original string to intercept the characters after ..

Answer 2

I don’t have MySQL at hand, but you can do this in Oracle:

select substr(PATH, instr(PATH, '.') + 1) from 表名

As for MySQL, you can just check if there are corresponding functions.