Help -> Unknown column in 'field list' error

dan22k

Hi,

I need some help that I just can't figure out. This should be easy, but I can't figure it out. I'm running PHP version 4.3.3 and MySQL version 4.0.18-standard.

This is basically an update statement and it works when I hardcode the following, it puts the string foo into GroupName at the specified GroupID.

$sql = 'UPDATE MainGroup SET GroupName = \'foo\' WHERE GroupID = '.$whichmod.' LIMIT 1 ;'
. ' ';

I have a string foo in variable $GroupName with the following query. I get the following error.

$sql = 'UPDATE MainGroup SET GroupName = '.$GroupName.' WHERE GroupID = '.$whichmod.' LIMIT 1 ;'
. ' ';

Unknown column 'foo' in 'field list'
Couldn't execute query: UPDATE MainGroup SET GroupName = '.foo.' WHERE GroupID = '.6.'

And this is another variation i've tried. with the following error.

$sql = 'UPDATE MainGroup SET GroupName = $GroupName WHERE GroupID = '.$whichmod.' LIMIT 1 ;'
. ' ';

Unknown column '$GroupName' in 'field list'
Couldn't execute query: UPDATE MainGroup SET GroupName = '.foo.' WHERE GroupID = '.6.'

I feel like i've tried every variation. I've just recently begun coding in php with mysql after a year or so layoff, so this feels like a problem I should have been able to figure out by know, but I haven't.

Any and all help would be appreciated.

thanks,

dan k.

rachel2004

Dump out your table structure with the column names (exactly as they appear in the table) and the data types.

Let's start there and see if we can troubleshoot this.

Also, is there a reason you have dots on either side of the variable $whichmod in your first $sql statement? I don't see what they are doing for you in this case.

You also do not need the semicolon after your LIMIT clauses. You only need the semicolon to close out your $sql variable.

dan22k

Hi,

It's a small table. GroupID unsigned int auto_increment and GroupName char(40)

The reason for the dots on either side $whichmod is simply because I found that type of example in a few book sources and when I added it, $whichmod finally worked the way I wanted it to. Unfortunately, all I could find were examples of it and I couldn't figure out what the syntax meant. I figured it was some sort of concatenation.

Thanks for your help. Let me know if there is more information I can provide.

rachel2004

So...

$GroupName = "foo";

$sql = "UPDATE MainGroup
SET GroupName = '$GroupName'
WHERE GroupID = '$whichmod'
LIMIT 1";

Try the above and see if it works. I removed all of your dots. Yes, the dots in PHP are for concatenation, but I couldn't see them being useful in your syntax, unless there's something I'm not aware of with your MySQL build.

Also, I wasn't sure what was up with your double semicolons near the end, so I have done away with that too. You actual UPDATE statement looked fine... just minor blemishes with the dots and semicolons.

Try it now and post again.

dan22k

It worked. Thank you Rachel. I think when I ran into some minor problems at first, i began to out think myself.

I appreciate the help.

Thanks again,

Dan

rachel2004

You bet. Happy coding. ;-)