Re: proposal: schema variables

Hi

st 20. 11. 2024 v 14:29 odesílatel Marcos Pegoraro <marcos(at)f10(dot)com(dot)br>
napsal:

> Em ter., 19 de nov. de 2024 às 16:15, Pavel Stehule <
> pavel(dot)stehule(at)gmail(dot)com> escreveu:
>
>> I wrote POC of VARIABLE(varname) syntax support
>>
>
> Not related with POC of VARIABLE but seeing your patches ...
>
> Wouldn't it be better to use just one syntax and message for what to do ON
> COMMIT ?
>
> When creating a new variable you use
> CREATE VARIABLE ... ON COMMIT DROP | ON TRANSACTION END RESET
>
> On PSQL \dV+ you show
> Transactional end action
>
> Maybe all them could be just ON COMMIT
> CREATE VARIABLE ... [ON COMMIT {NO ACTION, DROP, RESET}] and \dV+ just "on
> commit" on title column
>

ON COMMIT DROP is related to temporary objects. In this case, you don't
need to think about ROLLBACK, because in this case, the temp objects are
removed implicitly.

ON TRANSACTION END RESET can be used for non temporary objects too. So this
is a little bit of a different feature. But the reset is executed if the
transaction is ended by ROLLBACK too. So using a syntax just ON COMMIT can
be a little bit messy. TRANSACTION END is more intuitive, I think. If I
remember there was a proposal ON COMMIT OR ROLLBACK, but I think
TRANSACTION END is better and more intuitive, and better describes what is
implemented. I can imagine to support clauses ON COMMIT RESET or ON
ROLLBACK RESET that can be used independently, but for this time, I don't
want to increase a complexity now - reset is just at transaction end
without dependency if the transaction was committed or rollbacked.

Regards

Pavel

> regards
> Marcos
>