On Mon, May 24, 2010 at 9:27 PM, Stephen Frost <sfrost@snowman.net> wrote:
> * KaiGai Kohei (kaigai@ak.jp.nec.com) wrote:
>> We have two options; If the checker function takes the list of RangeTblEntry,
>> it will be comfortable to ExecCheckRTPerms(), but not DoCopy(). Inversely,
>> if the checker function takes arguments in my patch, it will be comfortable
>> to DoCopy(), but ExecCheckRTPerms().
>>
>> In my patch, it takes 6 arguments, but we can reference all of them from
>> the given RangeTblEntry. On the other hand, if DoCopy() has to set up
>> a pseudo RangeTblEntry to call checker function, it entirely needs to set
>> up similar or a bit large number of variables.
>
> I don't know that it's really all that difficult to set up an RT in
> DoCopy or RI_Initial_Check(). In my opinion, those are the strange or
> corner cases- not the Executor code, through which all 'regular' DML is
> done. It makes me wonder if COPY shouldn't have been implemented using
> the Executor instead, but that's, again, a completely separate topic.
> It wasn't, but it wants to play like it operates in the same kind of way
> as INSERT, so it needs to pick up the slack.
I think this approach is definitely worth investigating. KaiGai, can
you please work up what the patch would look like if we do it this
way?
Thanks,
--
Robert Haas
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