3 ms·

There's a bit more explanation here https://dba.stackexchange.com/a/59490/167040 https://dba.stackexchange.com/a/59490/167040 about why the trick works. MySQL c

• Sesse__ 4y ago
  To be clear: MySQL cannot use an index to directly seek past the first OFFSET rows; you still have O(n) behavior for OFFSET n. But you can use a covering index scan for the rows that you skip, which especially for InnoDB is somewhat cheaper than getting the full row. I guess this is what the technique is about. Edit: Indeed, this technique is seemingly for converting a regular query to a self-join, ie. a LIMIT m OFFSET n => (a LIMIT m OFFSET n) JOIN a, which is allowed as long as you have a unique constraint on the column you're joining on. I had assumed it actually wanted to convert something that was already a join.