Re: About union sql Mysql 4.x

[HALIL DEMIREZEN <suppressed>]

What if i want to list all the records not limiting them to a constant?



------------------------------------------------------------
Halil Demirezen 
System Support Engineer/ Sistem Destek Muhendisi 
Mobile Tel/Cep Tel: +90(543) 502 04 42
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Gleb Paharenko <suppressed> 
05.12.2005 12:19

To
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cc

Subject
Re: About union sql  Mysql 4.x






Hello.



>From http://dev.mysql.com/doc/refman/5.0/en/union.html:



"ORDER BY for individual SELECT statements within parentheses has an

effect only when combined with LIMIT. Otherwise, the ORDER BY is

optimized away."





Therefore you're getting the same results, because ORDER BY doen't

work for your query.







HALIL DEMIREZEN wrote:

> Hi,

> 

> I am trying to run an sql query such as below to list items=x randomly 
and 

> then items != x randomly.. 

> 

> 

> mysql> (select * from tablea where item=1 order by rand()) union all 

> (select  * from tablea where item != 1 order by rand());

> 

> but the result is not as expected. rand() seems not to be working...

> 

> What can be the problem? or what can be the difference between my will 
and 

> the exact result of the query?

> 

> Thanks..

> 

> 

> ------------------------------------------------------------

> Halil Demirezen 

> System Support Engineer/ Sistem Destek Muhendisi 

> Mobile Tel/Cep Tel: +90(543) 502 04 42

> E-Mail/E-Posta: suppressed

> -----------------------------------------------------------

> 



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