Re: 3.23.51 LIMIT efficiency problem

[Benjamin Pflugmann]

Hi.

On Wed 2002-06-19 at 20:03:32 -0600, mark_hazen@stripped wrote:
[...]
> But when I run 20 million rows into the dataset, it really slows down.
> (pretend the commas aren't there)
> SELECT a FROM b LIMIT 20,000,000, 1,000,000
> 
> Why would it slow down?  We're dealing with a fixed-length table here.  This
> is just mathematics to figure out where row 20,000,000 is.

And how do you know, how many deleted records are in the range, which
you have to skip?

And as someone else pointed out, without an ORDER BY the query you do
is meaningless, as the implied order undefined (i.e.  the order may
change without notice).

Bye,

	Benjamin.

-- 
benjamin-mysql@stripped