Check if value is already in db

[Anon]

Greetings,
I am looking for the most efficient way to check and see if an inputed email (via form) is already in the database under the column 'Email'. Any help would be greatly appretiated.

Thanks

[Anon]

Something like this?:

$already_in_db = mysql_result(mysql_query("select count(*) from <table> where <field> = '$email';"),0,0);

if($already_in_db > 0) {
// email is already in database
}

.. greetings,

Stephan

[Anon]

mysql_result(mysql_query(

Oy! I hope you meant that for demo purposes, and just accidentally left off the "error checking omitted" disclaimer. The problem with doing it this way is that if something does go wrong then you get a cascade of error messages about invalid result index, etc.

I know it's boring and tedious, but there isn't a good substitute for checking valid results one by one:

if (!($result = mysql_query(...)))
&nbsp;&nbsp;&nbsp;{
&nbsp;&nbsp;&nbsp;// your own user-friendly error handling here
&nbsp;&nbsp;&nbsp;}
else

[Anon]

Well, if you know the query is right there's nothing much to go wrong, really. But (of course) you should check everything...I'm just lazy 😉

Greetings,

Stephan