I have a table with say 20 rows each with a number for display order (1-20).
SELECT * FROM `mytable` ORDER BY `display_order` DESC;
From an adm
You could create a temporary table and populate with the primary key of the rows you want to change, and the new values of display_order for those rows, then use the multi-table version of UPDATE to update the table in one go. I wouldn't assume that this is faster, however, not without testing both approaches.