Rails where condition with nil value

Question

I found out that using where with symbol :my_id => nil and using old school one with ? is different. Could anyone explain me why?

MyTable.where(\"my_id = ? \", n         


        

Answer 1

The correct SQL syntax is my_id IS NULL, so if you change your first snippet to the following it will work:

MyTable.where("my_id IS ?", nil).first

Both syntaxes are perfectly fine. It's up to your own preference. However, if it's a parameter and you don't know whether it will be nil or not, you'd better use:

MyTable.where(:my_id => parameter).first