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Re: rownum-Problem
Posted by: Anders Karlsson
Date: December 22, 2004 01:59PM

This is that, a ROWNUM in Oracle is the sequential ID of the row as it is retrieved. So you cannot do:
SELECT * FROM sometable WHERE rownum = 17;
as with this condition, you will never get to row 17, as to find a row 17, you first have to find rows 1 to 16, which you have already stated that you don't want. The same reasoning goes for 57 also :-)
At least this is how rownum worked in the good old days. And nothiing wrong with that, as long as you know how it works.
To do what you want to do in MySQL is actually much MUCH easier. Just do this:
SELECT * FROM mytable ORDER BY rand() LIMIT 200;
That's it...

/Karlsson

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