Andres Freund writes:
> And arguably there's a fair bit of redundancy in pg_attribute, just
> because it's convenient for tupledescs. Given that pg_attribute very
> commonly is the largest catalog table by far, that very well could use
> some attention. Without tupdescs in mind, there's really
On 2018-08-23 11:04:30 -0400, Tom Lane wrote:
> "David G. Johnston" writes:
> > On Monday, August 20, 2018, Wu Ivy wrote:
> >> Why are SELECT query never marked nullable?
>
> > Basically the nullability property is used by the planner for optimization
> > during the joining of physical tables.
"David G. Johnston" writes:
> On Monday, August 20, 2018, Wu Ivy wrote:
>> Why are SELECT query never marked nullable?
> Basically the nullability property is used by the planner for optimization
> during the joining of physical tables. As soon as you try outputting
> columns the ability to
Thanks for the response. Really appreciate it!
Regards,
Ivy
2018-08-20 10:40 GMT-07:00 David G. Johnston :
> On Monday, August 20, 2018, Wu Ivy wrote:
>>
>> Thanks for the quick respond.
>> Why are SELECT query never marked nullable? For nullable columns, when I
>> call SPI_getvalue(), the
On Monday, August 20, 2018, Wu Ivy wrote:
>
> Thanks for the quick respond.
> Why are SELECT query never marked nullable? For nullable columns, when I
> call SPI_getvalue(), the result (in char*) is NULL. I don’t think I’m too
> clear on the definition of *attnotnull*. Can you give me a example
Hi tom,
Thanks for the quick respond.
Why are SELECT query never marked nullable? For nullable columns, when I call
SPI_getvalue(), the result (in char*) is NULL. I don’t think I’m too clear on
the definition of attnotnull. Can you give me a example in which the tupleTable
is can be marked
Wu Ivy writes:
> I’m currently building a Postgres C extension that fetch data from a Postgres
> table.
> Since the table can be large, in order to prevent memory overrun, I use
> SPI_cursor_fetch to fetch chunks of data. The result rows are saved in
> SPITupleTable* SPI_tuptable and
Hi developers,
I’m currently building a Postgres C extension that fetch data from a Postgres
table.
Since the table can be large, in order to prevent memory overrun, I use
SPI_cursor_fetch to fetch chunks of data. The result rows are saved in
SPITupleTable* SPI_tuptable and attributes are
