Re: TABLESAMPLE patch

On 22/12/14 20:14, Jaime Casanova wrote:
> On Thu, Dec 18, 2014 at 7:14 AM, Petr Jelinek <petr(at)2ndquadrant(dot)com> wrote:
>> Hi,
>>
>> v2 version of this patch is attached.
>>
>
> a few more tests revealed that passing null as the sample size
> argument works, and it shouldn't.

Fixed.

> in repeatable it gives an error if i use null as argument but it gives
> a syntax error, and it should be a data exception (data exception --
> invalid repeat argument in a sample clause) according to the standard

Also fixed.

>
> also you need to add CHECK_FOR_INTERRUPTS somewhere, i tried with a
> big table and had to wait a long time for it to finish

Ah yeah, I can't rely on CHECK_FOR_INTERRUPTS in ExecScan because it
might take a while to fetch a row if percentage is very small and table
is big... Fixed.

Attached is v3 which besides the fixes mentioned above also includes
changes discussed with Tomas (except the CREATE/DROP TABLESAMPLE
METHOD), fixes for crash with FETCH FIRST and is rebased against current
master.

--
Petr Jelinek http://www.2ndQuadrant.com/
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