How to improve sql query security using php?

Hi All, Great list! I have a simple html form which accepts an email address and password. I run this query: SELECT $emailfield, $passwordfield FROM $userstable WHERE $emailfield = '$loginemail' but what if the user enters the character "%@%", or other nasty things for the variable called $loginemail? I understand client side Javascript can be easily defeated, and that a LIMIT 1 will work -but not in other queries - which is what I will need. I don't want crackers piping out my complete data set. I need to get a better handle on this security issue. What's the BEST thing I can do here to improve my sql security using php? Regards, Richard Creech http://dreamriver.com richardc@dreamriver.com Phone 250.744.3350 Pacific Time