How to Correctly Increment a Value in a MySQL UPDATE Query?

Incrementing Value in MySQL Update Query

You've encountered an issue while trying to increment a value in your MySQL update query. Your code:

mysql_query("
    UPDATE member_profile 
    SET points= '" . $points . "' + 1 
    WHERE user_id = '" . $userid . "'
");

is not incrementing the points column as expected. Instead, it resets the value to 1.

Solution

The correct way to increment a value in a MySQL update query is by simply incrementing the existing value in the database. Here's the corrected code:

$sql = "UPDATE member_profile SET points = points + 1 WHERE user_id = ?";
$db->prepare($sql)->execute([$userid]);

This code uses prepared statements, which is a more secure and efficient way to execute SQL queries. It increments the points column by 1 for the specified user_id.

Additional Considerations

• Use prepared statements for better security and performance.
• Ensure that the points column is numeric to allow for arithmetic operations.
• Handle errors and exceptions in your code to prevent unexpected outcomes.

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