"User Sortable Items" UPDATE-ed to Database

I want to use this jQuery-UI-sortable in a project

What is the best practice to UPDATE the database after the user has finished sorting it?

Should I开发者_如何学C update on every release? OR have the user sort first and then press "Save"?

Also how do I retrieve the new order of the items and then update the database?

I'm thinking JSON Array + hidden form for the ID but I'm still confused. Thanks

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Yes, put a button "Save", automatically saving at each release is not only dangerous but also very confusing for the user, a "Save" button is straightforward.

As for how, yeah, a JSON array that you send to your back-end and that's it.