Difference in datediff function (mssql vs mysql)

Hey guys,

there is a difference in the functionality of the DATEDIFF() function between MySQL and MSSQL.

$additionalExpression = $appointment_query->func()->dateDiff([$appointment_query->func()->now(), 'Appointments.begin' => 'identifier']);

This works for me in MSSQL, but in MySQL you have to switch the args to get the same result:

$additionalExpression = $appointment_query->func()->dateDiff(['Appointments.begin' => 'identifier', $appointment_query->func()->now()]);

Is that a bug? Checked in cakephp 4.4.17

Best regards
Marc