I have been told that using this in the array:
'orderby' => 'rand'
will cause this:
Ordering by random is extremely expensive to query, involving creating temporary database tables, and scans, as it has to copy the entire posts table, then randomly re-order the posts, then finally do the actual query on the new table before destroying it.
And I have been advised:
It’s much easier to ask for the first post that occurs after a random date.
Can anyone elaborate on this?
Is there an array code line that will do the above?
Any resource regarding this would be very appreciated.