In fact the values to be looked-up will come numerically sorted (probably if the record IDs in db are really ordered by their numeric ID), so sorting the values in the array would mean that only first element is deleted.
So it seems that I can only ask whether the value to be looked up equals just the first item of the array! How only could miss it? Tx for pointing the possibility of ordering.
Undefs are ignored during the search, so their presence doesnt slowdown the procedure?

In reply to Re^2: Testing if an array contains a value and then deleting it in most efficient way by karpatov
in thread Testing if an array contains a value and then deleting it in most efficient way by karpatov

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