Member Avatar for demontro

Hey Guys i just was asking if i had data called zf and table cq_user and there is coulmn called emoney and i wanna increase This emoney Value By sumbit Like Increase at php page...

but i need This emoneyvalue if it's 100 i need to increase it by 10 so it's will be 110...

i dont want all id's being same emoney value but same emoney increase value and Thanks all and iam waiting for any solve and Thanks

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  • Latest Post Latest Post by silviuks

Dani AI

Generated

As asked, you want to add a fixed amount to a single user’s emoney rather than overwrite every row. pointed out a direct UPDATE — that works, but without a WHERE clause it changes every row. Use a WHERE to target the user, validate inputs, and use a prepared statement to avoid injection. If multiple requests can happen at the same time, either (a) do the increment in one server-side statement so it is atomic, or (b) lock the row in a transaction, read the current value, compute the new value, then write it.

Example using PDO with a row lock (safe for InnoDB):

$pdo->beginTransaction();

$stmt = $pdo->prepare('SELECT emoney FROM cq_user WHERE id = ? FOR UPDATE');
$stmt->execute([$id]);
$current = $stmt->fetchColumn();

if ($current === false) {
    $pdo->rollBack();
    // handle missing user
}

$new = (int)$current + (int)$delta;

$upd = $pdo->prepare('UPDATE cq_user SET emoney = ? WHERE id = ?');
$upd->execute([$new, $id]);

$pdo->commit();

Notes and cautions:

  • Always validate/cast $id and $delta as integers and check for negative or overflow values.
  • SELECT ... FOR UPDATE requires InnoDB; MyISAM does not support row-level locking.
  • For high concurrency, prefer a single atomic UPDATE on the server (it avoids the select/update round trip).
  • Log every change in a separate transactions/audit table (user_id, delta, old_value, new_value, timestamp, reason) so you can trace adjustments.
  • Check rowCount() or affected rows to confirm the update succeeded and handle errors with try/catch and rollbacks.

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Member Avatar for demontro

So Guys any advice?!

Member Avatar for silviuks

try this: update cq_user set emoney = emoney + 10

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