Re: [HACKERS] Cube extension point support // GSoC'13

Hello

There is new version of patch. I have separated ordering operators to different patch
(https://commitfest.postgresql.org/action/patch_view?id=1243),fixed formatting issues and implemented backward
compatibilitywith old-style points in cube_is_point() and cube_out(). 

Also comparing output files I've discovered that this four files is combination of two types of different behavior:

1) SELECT '-1e-700'::cube AS cube;
can be (0) or (-0)

2) Amount of zeros in exponent of floating point, i.e. SELECT '1e27'::cube AS cube;
 can be (1e+027) or (1e+27)

On my system (OSX) it is second option in both situations. I've also tested it on FreeBSD 9.0 and Ubuntu 12.04 with the
sameresults. So is there some ideas how can I reproduce such results? 

Stas.



On Sep 16, 2013, at 10:48 AM, Heikki Linnakangas wrote:

> On 12.07.2013 14:57, Stas Kelvich wrote:
>> Hello.
>>
>> here is a patch adding to cube extension support for compressed representation of point cubes. If cube is a point,
i.e.has coincident lower left and upper right corners, than only one corner is stored. First bit of the cube header
indicateswhether the cube is point or not. Few moments: 
>>
>> * Patch preserves binary compatibility with old indices
>> * All functions that create cubes from user input, check whether it is a point or not
>> * All internal functions that can return cubes takes care of all cases where a cube might become a point
>
> Great!
>
> cube_is_point() needs to still handle old-style points. An NDBOX without the point-flag set, where the ll and ur
coordinatesfor each dimension are the same, still needs to be considered a point. Even if you are careful to never
constructsuch structs in the code, they can be present on-disk if you have upgraded from an earlier version with
pg_upgrade.Same in cube_out(). 
>
>> * Added tests for checking correct point behavior
>
> You'll need to adjust all the expected output files, not only cube_1.out.
>
>> Also this patch includes adapted Alexander Korotkov's patch with kNN-based ordering operator, which he wrote for
postgresql-9.0beta1with knngist patch. More info there
http://www.postgresql.org/message-id/AANLkTimhFaq6hCibRnk0tlcQMIyhYWHwAQ2ZD87wbH86@mail.gmail.com
>
> To make review easier, it would be better to keep that as a separate patch, actually. Could you split it up again,
please?
>
> - Heikki