Обсуждение: regression tests

Hi,
   I don't see the regression tests running any index-hash operations.
What am I missing?

-- 
Cheers,    Jeremy

On Fri, Sep 6, 2013 at 3:34 AM, Jeremy Harris <jgh@wizmail.org> wrote:
>    I don't see the regression tests running any index-hash operations.
> What am I missing?

What's an index-hash operation?

...Robert

On 06/09/13 15:44, Robert Haas wrote:
> On Fri, Sep 6, 2013 at 3:34 AM, Jeremy Harris <jgh@wizmail.org> wrote:
>>     I don't see the regression tests running any index-hash operations.
>> What am I missing?
>
> What's an index-hash operation?


Ones that hit tuplesort_begin_index_hash()
-- 
Cheers,   Jeremy

On Fri, Sep 6, 2013 at 1:34 PM, Jeremy Harris <jgh@wizmail.org> wrote:
>> What's an index-hash operation?
>
> Ones that hit tuplesort_begin_index_hash()

Oh.  Well, it looks to me like that function can only get called when
building a hash index.  Specifically, according to the comment in
hashbuild(), a hash index projected to be larger than shared_buffers.
The regression tests are generally designed to work on small amounts
of data since they need to run quickly, so this isn't too surprising.
Hash indexes are a somewhat underwhelming feature anyway, since btrees
typically perform as well or better, and since hash indexes are not
WAL-logged and therefore can be corrupted on a crash.

-- 
Robert Haas
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