Programming stuff: Bash, Linux, SQL and Java

….not anymore, if you use IF.

there are cases where you can get rid of OR and get better performance in mysql.
here is a case a table:
book
id
french_name
engl_name

the books have only one name and only one, the other being null
you have a form on your web page and want to do a search for the books that contain a certain substring of characters. the client wants to retrieve both english and french name that contain that substring.

first shot: select * from book where french_name like ‘%CHARS%’ or engl_name like ‘%CHARS%’

this is very expensive.
the better solution:
select * from book where if(french_name is null,engl_name,french_name) like ‘%CHARS%’

on my system is 2 times faster.