Check if value exists before inserting into MySQL DB in a PHP script

mysql, php

Solution

Create a UNIQUE key on the fields you care about, and detect the integrity error after the fact.

Problem

I've looked for similar questions with no success. I have this piece of code: form1.php ``` $query = "INSERT INTO table1 "; $query .= "(fname, lname, mail)"; $query .= " VALUES "; $query .= "('".$_POST[fname]."', '".$_POST[lname]."', '".$_POST[mail]."')"; $result = mysql_query($query) or die ("Query Failed: " . mysql_error()); ``` And I want that the script will check if the value inserted exists in the corresponding column, and throw an error if it does. any ideas?

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