Updating sequence of numbers (display order) using PHP & MySQL
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I have a int(11) `DisplayOrder` column in my database of slideshow items which tells my code what order to display the items in. An admin can update the order with a form, changing, for example, number 20 to number 3. Without forcing the user to manually find number 3 and swap it with 20, **is there an easy way to update the sequence of numbers in the database?** Either using MySQL, or changing items in in `array()` before sending a query.

I've searched and searched, and there doesn't seem to be many solid answers. The issue is that I currently have 400 rows, and that number will grow. I don't really want to have to do 400 updates every time the order changes. **Is there a better way?** Are there existing scripts?