Re: BUG #8568: PLPGSQL Documentation For CASE Is incorrect

Dne 30.10.2013 1:29 "David Johnston" <polobo@yahoo.com> napsal(a):
>
> joshuadburns wrote
> > Every example within the PLPGSQL "control structures" documentation
states
> > that the proper syntax for closing a "CASE" statement is to use "END
> > CASE;"
> > however in reality, on every version of PostgreSQL I can my hands on,
"END
> > CASE;" throws the following exception:
>
> User error, though understandable.
>
> pl/pgsql CASE requires "END CASE", SQL CASE just uses "END"
>
> DO $$
> DECLARE val integer;
> BEGIN
> val := 2;
>
> CASE val
> WHEN 1 THEN RAISE NOTICE 'Got 1';
> WHEN 2 THEN RAISE NOTICE 'Got 2';
> END CASE;
>
> END;
> $$;
>
> Your examples were making use of SQL "CASE" expressions which do not
accept
> "END CASE" but "END".
>
> A pl/pgsql CASE must be the first token of an expression (using the term
> loosely) since its purpose is to act as flow-control.  The sames goes for
> IF.

It is just wrong. Plpgsql statements cannot be nested inside expression.

Plpgsql doesn't know only expression statemenst yet, so first token is
statement reserved keyword ever.

>
> There are a number of constructs and keywords in pl/pgsql that behave
> slightly differently than their counter-parts in pure SQL.
>
> David J.
>
>
>
>
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