>>> DECLARE @var EXTERNAL
>>
>> I do not know what you mean by 'EXTERNAL'.
>
> it means "used as shared in session"
Shared by whom? There is no such thing in the proposal I have made on the
wiki or in mails. In the proposal variables are private to the role which
creates them.
>> It is possible to find "some" typos, depending on the code: you can check
>> that a variable is both assigned and used somewhere, otherwise it is very
>> probably a typo. Perl does that *statically*, before executing a script.
>
> "Before execution" .. I am speaking "without execution".
Before execution is also without execution. You can run "perl -c" to get
the warning.
> theoretically, if you check all possible functions, you can find some
> issues - but you have to check all function on server.
Yes, sure. It seems to be the same with your proposal: if a hidden
function drops and recreates a session variable with a different type, or
changes its permission, then some static checks are void as well, that is
life. Also, a SQL function may access and modify the variables
unexpectedly, that would be missed by a PL/pgSQL analysis tool... There is
no miracle.
Basically, there may be issues even if static analysis tools says that all
is well.
> Elsewhere you cannot to find typo in DECLARE statement.
Indeed, probably there exists some class of typos that may not be found by
some static analysis implementations on PL/pgSQL functions which uses
basic session variables.
By the way, are you planing to contribute to the wiki?
https://wiki.postgresql.org/wiki/Variable_Design
--
Fabien.