Re: Execute ignoring cursor? - Mailing list pgsql-hackers

From Pavel Stehule
Subject Re: Execute ignoring cursor?
Date
Msg-id CAFj8pRDZnekzDUZSWruuVcWfxR8J1jKrLxzkiLZeGJ1_9XJaVA@mail.gmail.com
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In response to Re[2]: [HACKERS] Execute ignoring cursor?  (nummervet nummervet <nummervet@mail.ru>)
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2016-04-11 16:31 GMT+02:00 nummervet nummervet <nummervet@mail.ru>:
Oh. That doesn't work for me as i generate the query dynamically and don't know their structure...
Maybe there is an easy way to get the cursor structure (column - value, column - value....)?
Or should i give up on cursors and try something else? Some Google search hint that hstore could be my saviour :)

maybe hstore, or json, or C extension - I wrote plpgsql toolbox  https://github.com/okbob/pltoolbox . Another way is using PLPerl, PLPythonu. PLpgSQL is strongly strict language - it is not designed for dynamic tasks.

Regards

Pavel
 

Понедельник, 11 апреля 2016, 16:10 +03:00 от Pavel Stehule <pavel.stehule@gmail.com>:




2016-04-11 13:11 GMT+02:00 nummervet nummervet <nummervet@mail.ru>:
Ok, now i am getting this:
ERROR:  could not identify column "151" in record data type

Raise notice show that the column exists.
Any other way around it?


hmm - it doesn't work for generic record - it should be typed row value.

postgres=# create table foo("123" int);
CREATE TABLE

postgres=# create table boo("123" int);
CREATE TABLE

insert into boo values(20);
INSERT 0 1

postgres=# do $$
declare r boo; -- cannot be generic record
begin
  for r in select * from boo
  loop
    execute $_$insert into foo values($1."123")$_$ using r;
  end loop;
end;
$$;
DO

Regards

Pavel

 

Пятница, 8 апреля 2016, 18:24 +03:00 от Pavel Stehule <pavel.stehule@gmail.com>:




2016-04-08 16:46 GMT+02:00 nummervet nummervet <nummervet@mail.ru>:
That didn't work for me:

ERROR:  syntax error at or near "$"
LINE 1: ...ibute_id, set_id ) (select $."151", '...

should be $1

Regards

Pavel
 


Пятница, 8 апреля 2016, 17:25 +03:00 от Pavel Stehule <pavel.stehule@gmail.com>:


Hi

2016-04-08 16:17 GMT+02:00 nummervet nummervet <nummervet@mail.ru>:
Hello. Didn't find dedicated plpgsql list, so decided to post question here.
I am trying to create a  function that will pick up some values from cursor and execute them as a dynamic query.
However, once i use EXECUTE, its seems to be ignoring the existence of cursor and try to pick up values from table.
Basically:

insert into mytable ( value, attribute_id, set_id ) (select rec."151", '201', '1')

works, but

execute 'insert into mytable ( value, attribute_id, set_id ) (select rec."151", ''201'', ''1'')'

Dynamic queries are executed in own space and there are not direct access to plpgsql variables.

please, try: execute 'insert into mytable ( value, attribute_id, set_id ) (select $1."151", ''201'', ''1'')' using rec;

Regards

Pavel Stehule
 

fails with

ERROR:  missing FROM-clause entry for table "rec"
LINE 1: ...ibute_id, set_id ) (select rec."151",...

Is there any way around it? Or should i just give up and do it some other way?








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