Re: Strange limit and offset behaviour....

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От
Adam Rich
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Re: Strange limit and offset behaviour....
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0cbf01c9896e$005ecaf0$011c60d0$@r@sbcglobal.net
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Strange limit and offset behaviour.... Bjørn T Johansen <btj@havleik.no>
Re: Strange limit and offset behaviour.... "Adam Rich" <adam.r@sbcglobal.net>
Re: Strange limit and offset behaviour.... Bjørn T Johansen <btj@havleik.no>
Re: Strange limit and offset behaviour.... Grzegorz Jaśkiewicz <gryzman@gmail.com>
Re: Strange limit and offset behaviour.... Bjørn T Johansen <btj@havleik.no>
Re: Strange limit and offset behaviour.... Grzegorz Jaśkiewicz <gryzman@gmail.com>
> 
> I have the following sql:
> 
> SELECT * from table order by dato asc limit 20 offset 0
> 
> 
> This gives me different rows than the 20 first rows when running the
> following sql:
> 
> SELECT * from table order by dato asc
> 
> 
> Shouldn't the 20 first rows in the second sql statment be the same 20
> rows that is returned in the first statement
> or am I missing something?
> 

Not necessarily.  In your example query, if "dato" was not a unique
column, and there were some duplicates, the "top 20" values is not
a defined set.  Adding the offset clause might cause a different
query plan, resulting in a different ordering of the duplicate values.





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