Re: proposal: plpgsql pragma statement

On 3/7/19 3:19 AM, Pavel Stehule wrote:
> Hi
>
> čt 7. 3. 2019 v 8:03 odesílatel David Steele <david@pgmasters.net
> <mailto:david@pgmasters.net>> napsal:
>
>     On 2/4/19 8:12 PM, Pavel Stehule wrote:
>     >
>     >   attached rebased patch
>
>     This patch has gone through a few iterations but I don't think
>     there's
>     any agreement on what it should look like.  There's been no code
>     review
>     that I can see.
>
>     I think this should be pushed to PG13 at the least, perhaps returned
>     with comment or rejected.
>
>
> This patch is in this moment in this form interesting just for
> plpgsql_check's users.
>
> I cannot to move forward without this functionality .. I have a
> promise of review by some people from big company that uses
> plpgsql_check, but if there is not interest from commiter's side, then
> it is not time for pushing this patch today.
>
> On second hand, the proposed syntax is same like for autonomous
> transactions, so I believe, so this patch will come in few years.
>
> Please, wait few week, and then it can be rejected.
>
>


I have looked at the latest patch, but it seems inadequate unless I'm
misreading it. I think a general pragma mechanism should allow a pragma
just about anywhere. If the processor doesn't recognize the pragma it
ignores it, if it does it processes it in the appropriate context. That
could be for the next statement, the current block, or whatever.  If it
appears in the wrong context the processor should object.


For example, one of Ada's predefined pragmas is PAGE, which causes a
processor producing a program listing to emit a page feed. (Yes, I know,
probably silly, but you get the idea why this pragma can accur just
about anywhere.) There is also 'pragma Assert' which is more or less
like our Assert in C.

cheers


andrew


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