Update multiple rows with single query using MySQL and PHP - php

Question

<?php
$userData = array();
while (anything to create a loop) {
$value1 = $result1_from_loop;
$value2 = $result2_from_loop;
$value3 = $result3_from_loop;
$userData[] = '("'.$value1.'", "'.$value2.'", "'.$value3.'")';
} // THIS ENDS THE WHLE OR FOR LOOP
$query = 'INSERT INTO users (data1,data2,data3) VALUES' . implode(',', $userData);
mysql_query($query);
?>
The above code works perfectly for inserting multiple records into table users as seen above and it's very fast as well.
However, I am trying to use the same method to update after going through a loop as before. I have no idea how to achieve this.
I want something like this:
<?php
$userData = array();
while (Loop statement) {
$value1 = $result1_from_loop;
$value2 = $result2_from_loop;
$value3 = $result3_from_loop;
$userData[] = '("'.$value1.'", "'.$value2.'", "'.$value3.'")';
} // This ends the WHLE or FOR loop
$query = 'UPDATE users SET(data1,data2,data3) VALUES' . implode(',',$userData) WHERE data2=$value2
mysql_query($query);
I know the above code is not close to correct, syntax is even wrong. I just pasted it to show the idea of what I want achieved. In the WHERE statement how will data2 get to know the value of each $value2?

Answer 1

UPDATE uses a different format to INSERT. For UPDATE, your code should look something like this:
$query = 'UPDATE users SET data1 = $userData[0], data2 = $userData[1], data3 = $userData[2] WHERE data2=$value2';
Although just as a note, using mysql_query is not advised as it is deprecated (and will be removed altogether in later PHP versions) and your code is vulnerable to SQL injection. At a minimum I'd recommend using mysqli_query instead and looking into using prepared statements.