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From Dave Brosius <dbros...@mebigfatguy.com>
Subject Re: primary keys query
Date Fri, 11 May 2012 15:12:43 GMT
Inequalities on secondary indices are always done in memory, so without 
at least one EQ on another secondary index you will be loading every row 
in the database, which with a massive database isn't a good idea. So by 
requiring at least one EQ on an index, you hopefully limit the set of 
rows that need to be read into memory to a manageable size. Although 
obviously you can still get into trouble with that as well.



On 05/11/2012 09:39 AM, cyril auburtin wrote:
> Sorry for askign that
> but Why is it necessary to always have at least one EQ comparison
>
> [default@Keyspace1] get test where birth_year>1985;
>     No indexed columns present in index clause with operator EQ
>
> It oblige to have one dummy indexed column, to do this query
>
> [default@Keyspace1] get test where tag=sea and birth_year>1985;
> -------------------
> RowKey: sam
> => (column=birth_year, value=1988, timestamp=1336742346059000)
>
>


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