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From Jonathan Ellis <jbel...@gmail.com>
Subject Re: Range scan performance in 0.6.0 beta2
Date Mon, 29 Mar 2010 15:02:54 GMT
I see what you mean -- you have understood correctly.

On Mon, Mar 29, 2010 at 8:13 AM, Henrik Schröder <skrolle@gmail.com> wrote:
> On Mon, Mar 29, 2010 at 14:15, Jonathan Ellis <jbellis@gmail.com> wrote:
>>
>> On Mon, Mar 29, 2010 at 4:06 AM, Henrik Schröder <skrolle@gmail.com>
>> wrote:
>> > On Fri, Mar 26, 2010 at 14:47, Jonathan Ellis <jbellis@gmail.com> wrote:
>> >> It's a unique index then?  And you're trying to read things ordered by
>> >> the index, not just "give me keys with that have a column with this
>> >> value?"
>> >
>> > Yes, because if we have more than one column per row, there's no way of
>> > (easily) limiting the result.
>>
>> That's exactly what the count parameter of SliceRange is for... ?
>
> I thought that only limited the number of columns per key?
>
> We're using the get_range_slices method, which takes both a SlicePredicate
> (which contains a range, which contains a count) and a KeyRange (which also
> contains a count). Say that we have a bunch of keys that each contain 10
> columns, and we do a get_range_slices over those, how do we get the first 25
> columns? If we put it in the SliceRange count, we'll get all matching rows,
> and the 25 first columns of each, right? And if we put it in the KeyRange
> count, we'll get the 25 first rows that match, and all their columns, right?
>
> But if we have only one column per row, then we can limit the results the
> way we want to. Or have we misunderstood the api somehow?
>
>
> /Henrik
>

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