Okay, it turns out that mysql does not allow you to declare an "auto_increment" field unless it's going to be the primary key.

So don't use an auto_increment field. Use a date_time field instead (call it something like "create_date"), and whenever a new row is inserted, set its value with the "NOW()" function. Then you'll be able to "order by create_date desc limit 10".

You don't need an auto_increment field -- you just need "url" to be the primary key, and you need something chronological to sort on.

Update: About the 2nd part of your initial question: you could try to work out a two-stage query: find the "create_date" value for the row that is currently 10 rows "back" from the most recent row, then select all rows where create_date is greater than that value, and order by "Total".

But I think it would be a lot easier to do a single query ordered chronologically, store those into an AoA or AoH and let the perl script sort them based on "Total".

In reply to Re^3: UPDATE ON DUPLICATE and sorting by graff
in thread UPDATE ON DUPLICATE and sorting by coldfingertips

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