Re: Implement <null treatment> for window functions

Hi, patch applies and compiles, all included and external tests and
building of the docs pass.
After the last run of the cfbot, there are no any building warnings.
I am using last version in our testing environment with real data and I
didn't find any bugs,
so I'm marking this patch as ready for the committer in the commitfest app.

На сб, 9.01.2021 г. в 13:30 ч. Krasiyan Andreev <krasiyan(at)gmail(dot)com> написа:

> Hi, the building warning below is fixed now, no other changes. Also, I can
> confirm that the corner case with offset=0 in lead and lag works correctly.
>
> gcc -Wall -Wmissing-prototypes -Wpointer-arith
> -Wdeclaration-after-statement -Werror=vla -Wendif-labels
> -Wmissing-format-attribute -Wimplicit-fallthrough=3 -Wcast-function-type
> -Wformat-security -fno-strict-aliasing -fwrapv -fexcess-precision=standard
> -Wno-format-truncation -Wno-stringop-truncation -O2 -I../../../src/include
> -I/home/krasiyan/pgsql/postgresql/src/include -D_GNU_SOURCE
> -I/usr/include/libxml2 -c -o nodeWindowAgg.o
> /home/krasiyan/pgsql/postgresql/src/backend/executor/nodeWindowAgg.c
> /home/krasiyan/pgsql/postgresql/src/backend/executor/nodeWindowAgg.c: In
> function ‘WinGetFuncArgInPartition’:
> /home/krasiyan/pgsql/postgresql/src/backend/executor/nodeWindowAgg.c:3274:10:
> warning: ‘step’ may be used uninitialized in this function
> [-Wmaybe-uninitialized]
> 3274 | relpos += step;
> | ~~~~~~~^~~~~~~
> /home/krasiyan/pgsql/postgresql/src/backend/executor/nodeWindowAgg.c: In
> function ‘WinGetFuncArgInFrame’:
> /home/krasiyan/pgsql/postgresql/src/backend/executor/nodeWindowAgg.c:3531:10:
> warning: ‘step’ may be used uninitialized in this function
> [-Wmaybe-uninitialized]
> 3531 | relpos += step;
> | ~~~~~~~^~~~~~~
>
>
>
> На пт, 8.01.2021 г. в 2:02 ч. Vik Fearing <vik(at)postgresfriends(dot)org>
> написа:
>
>> On 1/1/21 10:21 PM, Zhihong Yu wrote:
>> > Krasiyan:
>> > Happy New Year.
>> >
>> > For WinGetFuncArgInPartition():
>> >
>> > + if (target > 0)
>> > + step = 1;
>> > + else if (target < 0)
>> > + step = -1;
>> > + else
>> > + step = 0;
>> >
>> > When would the last else statement execute ? Since the above code is
>> > for WINDOW_SEEK_CURRENT, I wonder why step should be 0.
>>
>> Hi.
>>
>> "lag(expr, 0) over w" is useless but valid.
>> --
>> Vik Fearing
>>
>