Re: indices not used

[Martin Luy]

The quotes were missing in the ean-query:

EXPLAIN(SELECT * FROM `products` WHERE isbn_13 > '9780000000000' AND isbn_13 < '9780000000002')

id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE products range ean ean 42 NULL 1 Using where


But I didn't find the reason for the factor query. It doesn't work with "ORDER BY id", too (id is of type integer and the primary key column). In another table (which has much less rows), the respective index is used with a similar query:

EXPLAIN(SELECT * FROM orders ORDER BY customer_id DESC)

id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE orders index NULL orders_customer_id 9 NULL 1061

Do I need to do "ALTER TABLE product ORDER BY factor", and do I still need "ORDER BY factor" in the query then?

Martin



Edited 1 time(s). Last edit at 05/25/2010 12:08PM by Martin Luy.