[SOLVED] Check it record exists in MySQL

[Hyperjase]

Hey guys,

 

I'm trying to knock a quick piece of code up to check it a record already exists in one table, if it does, stop the query and inform the user.

 

I've been looking around and using mysql_num_rows but no matter what i do, it keeps erroring out.

 

Here is what I have, all I need to check is that the data entered in the category form doesn't already exist in the table.

 

$result = mysql_query( "SELECT * FROM category.catname WHERE catname=".$_POST['category'] );
if (mysql_num_rows($result) > 0) {
    echo "Already exists";
exit;
	} else {

 

I think the mysql_query may well be wrong, but the table is in the category section, with catname being the row.

 

Thanks guys, your work is invaluable, specially to me!!!

 

Jason

[Maq]

If you used or die(mysql_error()) you would have gotten an error for this.

 

You need single quotes around the POST value you want to compare the column to.

 

Try:

 

   $result = mysql_query( "SELECT * FROM category.catname WHERE catname='{$_POST['category']}' );

[Mchl]

SELECT * FROM category WHERE catname = ?

 

category.catname means 'table `catname` in database `category`'

[premiso]

Don't forget the ending "

 

$result = mysql_query( "SELECT * FROM category.catname WHERE catname='{$_POST['category']}'" );

[Maq]

Yeah, those 2 things would help too... 

[Hyperjase]

Fantastic, thanks guys - that worked a treat.

 

I've used the above code too, error_reporting, just for future info.

 

Whilst I'm on this subject .... the bit where it says it exists .... between the curly braces - is there any way of making it "go-to" another part of the script ... this part - if (isset($_GET['addcat'])) { - then inputting a message above the same form to say that it already exists ... or can I just move the whole query to the start of the form?  I know that php evaluates everything before it outputs it ... so that should work?

 

Cheers!

 

Jason