Re: [RFC] Add an until-0 loop in psql - Mailing list pgsql-hackers

From Pavel Stehule
Subject Re: [RFC] Add an until-0 loop in psql
Date
Msg-id CAFj8pRDMdWs4dr7JKvmbsTAmhT0D1revCxyoY6QuyacYwH9MFA@mail.gmail.com
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In response to Re: [RFC] Add an until-0 loop in psql  (Corey Huinker <corey.huinker@gmail.com>)
Responses Re: [RFC] Add an until-0 loop in psql
List pgsql-hackers


2018-04-28 7:36 GMT+02:00 Corey Huinker <corey.huinker@gmail.com>:



What you don't see here is that you're using your psql process's available open file handles as a stack, and when you hit that limit psql will fail. If you remove that limit, then you get a bit further before psql segfaults on you. I think I got ~2700 files deep before that happened. Your stackage may vary.

I'm not saying this is a good solution, quite the contrary. I think the sane solution is right around the corner in Version 11.

Now if we just had a way of passing parameters into DO blocks...

I hope so there will be schema (temporal) variables:

create temp variable foo int default 10;

do $$
begin
  for i in 1..foo loop
    raise notice '%', i;
  end loop;
end;
$$;

That would be nice too.

A while back, somebody explained why implementing parameters in a DO block was so hard, but I don't recall why, and the search terms "do" and "parameter" don't really narrow things down.

I did it too. It is not too hard - there was not a agreement on syntax.

can be nice some like CTE

WITH PROCEDURE x(a int, b int) AS ... $$ SELECT x(10);

Maybe Oracle supports this syntax

Pavel
 

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