Re: Refactoring SysCacheGetAttr to know when attr cannot be NULL - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Refactoring SysCacheGetAttr to know when attr cannot be NULL
Date
Msg-id 1896001.1677767049@sss.pgh.pa.us
Whole thread Raw
In response to Re: Refactoring SysCacheGetAttr to know when attr cannot be NULL  (Daniel Gustafsson <daniel@yesql.se>)
List pgsql-hackers
Daniel Gustafsson <daniel@yesql.se> writes:
>> On 1 Mar 2023, at 00:20, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Also ... at least in assert-enabled builds, maybe we could check that
>> the column being fetched this way is actually marked attnotnull?

> We could, but that would limit the API to attnotnull columns, rather than when
> the caller knows that the attr cannot be NULL either due to attnotnull or due
> to intrinsic knowledge based on what is being extracted.
> An example of the latter is build_function_result_tupdesc_t() which knows that
> proallargtypes cannot be NULL when calling SysCacheGetAttr.

OK, if there are counterexamples then never mind that.  I don't think
we want to discourage call sites from using this function.

            regards, tom lane



pgsql-hackers by date:

Previous
From: Dave Cramer
Date:
Subject: Request for comment on setting binary format output per session
Next
From: Tom Lane
Date:
Subject: Re: Refactoring SysCacheGetAttr to know when attr cannot be NULL