Add (sum) variable to existing value in database

Question

I have database with column "kredit". I want to add $dobitak to kredit.

So if is in database kredit=10, and $dobitak=15 kredit+dobitak=25 but my code return me kredit=15 in database.

$sql = "UPDATE user
    SET  kredit='kredit' + '".$dobitak."'
    WHERE id='" . $info['user_id'] . "'";

What I need to change to get correct result in database?

Use back ticks or remove the single quotes,you are adding a string. — Mihai
– Mihai, Commented Jan 4, 2014 at 12:07
Remove single quotes arround the column SET kredit=kredit + '".$dobitak."' — M Khalid Junaid
– M Khalid Junaid, Commented Jan 4, 2014 at 12:08

user1844933 · Accepted Answer · 2014-01-04 12:07:59Z

3

try this ...

$sql = "UPDATE user
    SET  kredit=kredit + ".$dobitak."
    WHERE id='" . $info['user_id'] . "'";

Because for integer type field you need not enclose with "'"

answered Jan 4, 2014 at 12:07

user1844933

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1 Comment

If you want appreciate then choose this as correct answer... :)

GrahamTheDev · Accepted Answer · 2014-01-04 12:08:58Z

0

kredit = kredit + '". $dobitak ."'
WHERE id='" . $info['user_id'] . "'";

Remove the ' ' from around kredit

answered Jan 4, 2014 at 12:08

GrahamTheDev

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