updateTicket
Replaces the cached row for ticket (remove + re-add, so fields that became absent are dropped).
Return
true if a row existed and was replaced, false if the ticket was not in this index (no row is added in that case).
Replaces the cached row for ticket (remove + re-add, so fields that became absent are dropped).
true if a row existed and was replaced, false if the ticket was not in this index (no row is added in that case).