Re: PL/pgSQL: possible parsing or documentation bug?

"Albert REINER" <areiner@tph.tuwien.ac.at> writes:
> create Function IdOfPossiblyNewAuthor(text) returns int4 as '
>   declare
>     id int4;
>   begin
>     select id into id from author where name = $1;
>     raise notice ''ID found: %'', id;
>     if id is null then
>       insert into author (name) values ($1);
>       select currval(''author_id_seq'') into id;
>       raise debug ''Author inserted. ID: %'', id;
>     end if;
>     return id;
>   end;
> ' language 'plpgsql' with (IsCachable);

> Logically it is clear which "id" should be parsed as the variable,
> which as author.id,

No, it is not so clear.  Consider the following:
declare  x int4;  y int4;begin  x := ...;  select x + f1 into y from tab1 where ...;

The intent here is clearly to find a value tab1.f1 in tab1 and then
add the local variable x to form a value for the local variable y.

In general plpgsql will try to match an unqualified name to a variable
before it will consider whether it might be a field name.  If you don't
want that, qualify the field name:
    select author.id into id from author where name = $1;

Feel free to submit documentation updates to make this clearer...
        regards, tom lane