Re: poll: CHECK TRIGGER?

2012/3/9 Robert Haas <robertmhaas@gmail.com>:
> On Fri, Mar 9, 2012 at 5:09 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
>>> Well, that just means that it'd be a good idea for that function to be
>>> supplied by the same shared library that supplies the plpgsql execution
>>> functions.  There wouldn't need to be any connection that the core
>>> system particularly understands.  So, like Peter, I'm not quite sure
>>> what distinction is meant to be drawn by "internal" vs "external".
>>
>> internal - implement in core, external - implement in extension.
> [...]
>> I cannot to move plpgsql checker to extension, because there is
>> dependency on plpgsql lib, and this is problem. If I can do it, then I
>> did it
>
> I don't object to having this feature live in src/pl/plpgsql, and I
> don't think Tom's objecting to that either.  I just don't think it
> needs any particular support in src/backend.
>
>> I don't see a reason why we need a multiple checkers - checkers are
>> parametrised, so there are no real reason, But what statement will be
>> maintain this catalog - CREATE CHECK ? You need DROP, ALTER, .. it is
>> lot code too.
>
> If the checkers are written by different people and shipped
> separately, then a parameter interface does not make anything better.

ok - it has sense, but it has sense only with some "smart" statements
(like CHECK). Without these statements I have to directly call checker
function and then  concept of generalised checkers has not sense.

Pavel

>
> --
> Robert Haas
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