mysql 删除从字符串末尾开始的 2 个尾随点

Question

How do i remove trailing dots starting from the end of the string.

I tried a bunch of stuff like TRIM(TRAILING '.' FROM column ) and SUBSTRING but it doesn't fit the desired output due to my column value has a random length.

Here's my sample string:

 "www.facebook.com.102019.crt"

wanted to remove

".102019.crt" 

in my string and it should look like this

"www.facebook.com"

Answer 1

Assuming the inputs were always of the form:

www.domain.com
www.domain.net

You could just use SUBSTRING_INDEX here:

SELECT SUBSTRING_INDEX('www.facebook.com.102019.crt', '.', 3);

This returns:

www.facebook.com