vb.org Archive - View Single Post - "ORDER BY" without large table scans and filesort

Quote:

Originally Posted by KirbyDE

OK, this seems to be impossible but I thought I could ask anyway, maybe I overlooked smth. and somebody has the 1.000.000 $ answer

Let's say I got a table with several tenthousand records; the primary index as an auto-increment integer.
Now I want the last record.
I could do
[sql]SELECT * FROM table ORDER BY id DESC LIMIT 1[/sql]

But this causes large table scans ...

since there is no condition (WHERE and/or GROUP BY) - this query will be a full index scan

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X vBulletin 3.8.12 by vBS Debug Information
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