Control duplicate entries in Hook Post

Question

I'm in need of inserting a control query into a hook post to retrieve if there is duplicate data.

I am using a php query but the only reaction I have is that it continues to compute forever, is it possible that there are strings of CIVI seasoning more suitable for this task?

$check = mysql_query("SELECT * FROM table WHERE code = '$invoicenum'");
    $checkrows = mysql_num_rows($check);

   if ($checkrows > 0) {
WARNING
   } 
   else {
OK CONTINUE CHANGE
}

Regards

Answer 1

You're using mysql_query, which is deprecated in both PHP and modern versions of Civi. The code isn't running forever, it's failed with an error - you should be able to find that error, most likely in your CiviCRM log.

While you could use mysqli_query, the better choice is to use a wrapper, which should give at least partial future-proofing. Here's my (untested!) attempt at a rewrite:

Use:

$check = CRM_Core_DAO::executeQuery("SELECT * FROM table WHERE code = '$invoicenum'");

if ($check->fetch()) {
  // WARNING
else
  // OK
}

Note also that if you're using the post hook, the data has already been written to the database. I would put this in a validation hook or an API Wrapper hook if you're trying to prevent the data being written.