PostgreSQL went as far as release 10 without procedures.
Some third party resources written before 11 loosely conflate procedures with functions.
Some third party resources written before 11 accurately state PostgreSQL has functions but not procedures.
Referring to the PostgreSQL docs for 11 on, procedures have been added.
For someone like me, coming to the subject without much of a hinterland other than googling around, it seemed clear that there was a motivating case that caused Procedures to be added to PostgreSQL, but I was not sufficiently familiar with the domain to be able to readily intuit what it might have been.
For example, Procedures say they have no return value, yet Functions can return void. Not the same I agree, but I wouldn't be aware in which circumstances it mattered.
For me, perhaps the most useful thing would have been a small example highlighting the essential thing(s) that procedures can do that functions could not.
Robin
On Thu, 6 Aug 2020 at 11:32, Dave Cramer <davecramer@postgres.rocks> wrote:
On Tue, Aug 4, 2020 at 10:33:49AM +0000, PG Doc comments form wrote:
> The following documentation comment has been logged on the website:
>
> Page: https://www.postgresql.org/docs/11/sql-createprocedure.html
> Description:
>
> The information on procedures could helpfully include that the feature is
> new from PostgreSQL 11 and give an explanation of how it differs from
> functions. I found the information I needed here
> https://dba.stackexchange.com/a/262662, but I think it would really benefit
> others if the information was provided in the official documentation.
We don't normally mention what release added a features. However, I do
see your problem with finding that procedures can issue transaction
control statements. I see this for procedures:
https://www.postgresql.org/docs/12/xproc.html
but that has no mention of transactions, just a mention of using CALL,
then this pl/pgSQL section about transaction control mentions CALL:
https://www.postgresql.org/docs/12/plpgsql-transactions.html
Is this what you think needs improving?
Neither of those places mention that procedures cannot be called inside a transaction.
So ya I think there there is some room for improvement
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