How can I escape square brackets in a LIKE clause?

Question

I am trying to filter items with a stored procedure using like. The column is a varchar(15). The items I am trying to filter have square brackets in the name.

For example: WC[R]S123456.

If I do a LIKE 'WC[R]S123456' it will not return anything.

I found some information on using the ESCAPE keyword with LIKE but I do not understand how to use it to treat the square brackets as a regular string.

Answer 1

Instead of '\' or another character on the keyboard, you can also use special characters that aren't on the keyboard. Depending o your use case this might be necessary, if you don't want user input to accidentally be used as an escape character.

Answer 2

If you would need to escape special characters like '_' (underscore), as it was in my case, and you are not willing/not able to define an ESCAPE clause, you may wish to enclose the special character with square brackets '[' and ']'.

This explains the meaning of the "weird" string '[[]' - it just embraces the '[' character with square brackets, effectively escaping it.

My use case was to specify the name of a stored procedure with underscores in it as a filter criteria for the Profiler. So I've put string '%name[_]of[_]a[_]stored[_]procedure%' in a TextData LIKE field and it gave me trace results I wanted to achieve.

Here is a good example from the documentation: LIKE (Transact-SQL) - Using Wildcard Characters As Literals

Answer 3

The ESCAPE keyword is used if you need to search for special characters like % and _, which are normally wild cards. If you specify ESCAPE, SQL will search literally for the characters % and _.

Here's a good article with some more examples

SELECT columns FROM table WHERE 
    column LIKE '%[[]SQL Server Driver]%' 

-- or 

SELECT columns FROM table WHERE 
    column LIKE '%\[SQL Server Driver]%' ESCAPE '\'