Suppose I have the following query:
here the `user_name` field is primary key as well.
In the above, the user somename is retrieved through php. Anyway, my question is, if I know that there will only be one user of the same name - is it requrred to use LIMIT 1?
My brother says it's more efficient to do so, but I read somewhere that it may slow things down. But since it's just LIMIT 1 there shouldn't be much issue with speed. But I want to know what's the best practice.