select/display last inserted serial id in postgres

Question

in sql server I do like this:

insert into foo(name) values(\'bob\')
select @@identity;

so I get a query/scalar result displayed

how to

Answer 1

Get a specific sequence:

SELECT currval('name_of_your_sequence');

Get the last value from the last sequence used:

SELECT lastval();

Check the manual as well: http://www.postgresql.org/docs/current/static/functions-sequence.html

Edit: You could also use RETURNING in your INSERT:

INSERT INTO foo(id, name) VALUES(DEFAULT, 'bob') RETURNING id;

Answer 2

It would be

GET DIAGNOSTICS YourParam = RESULT_OID;

See here http://www.postgresql.org/docs/8.2/static/plpgsql-statements.html scroll down to 37.6.6. Obtaining the Result Status

asker edit: I tried this:

create or replace function aaa() returns int as $$ 
declare 
a int;
begin
insert into oameni values(default, 'aaa');
get diagnostics a = result_oid;
return a;
end;
$$ language plpgsql;

it always returns 0, you know what's wrong here?

Answer 3

A good way is using RETURNING id. Here is a short example using PL/pgSQL:

        DECLARE
        nivel1 RECORD;
        resultId BIGINT;
        BEGIN
          FOR nivel1 IN SELECT * FROM primary_table LOOP
            INSERT INTO second_table(id, field2, field3) VALUES (DEFAULT, "value2", "value3") RETURNING id INTO resultId;
            RAISE NOTICE 'Inserted id: %s', quote_literal(resultId);
          END LOOP;
        RETURN;
        END

It works for me!