----- Original Message -----
> From: "Akshay Suryavanshi" <akshay.suryavansh...@gmail.com>
> 
> I am not sure, but if its a MyISAM table, it should be ordered by the
> records insertion order, and in case of InnoDB it should be ordered
> by the clustered index, not necessarily it should be a defined one.

No.

The optimizer may choose to do a full table scan, or it may choose to use an 
index scan. That decision may change due to changes in the data, or because the 
next version of mysql you upgrade to has different (and hopefully better...) 
alghorithms, et cetera.

The ONLY way to ensure consecutive queries return your data in the same order, 
is specifying an order by clause.

Apart from that, I personally prefer to avoid the limit 0,10 /limit 11/20 
technique, because a) rows might have gotten inserted and/or deleted, and b) 
limit is applied to the full resultset.

Instead, order by the PK (or another unique index or combination of indices), 
remember the last record's value(s) and use that as starting point for your 
next query.



-- 
Unhappiness is discouraged and will be corrected with kitten pictures.

-- 
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe:    http://lists.mysql.com/mysql

Reply via email to