PHP Security question

Quick question from a PHP noob:

I want to put a password into a mysql db by hashing it first, and then sending the hash.  Is there a security risk here?  I don't know enough about where things are happening (client vs server, etc...) to know.

>>2
It's not a security risk if it's just a local socket, which is a fairly common case (web server and database server are on the same box).