Error working with Temporary Sequences in plpgsql in 8.1 (8.0 works fine)

On 1/17/06, Daniel Schuchardt <daniel_schuchardt@web.de> wrote:

Hi,

here is a testcase:

CREATE OR REPLACE FUNCTION testseq()
RETURNS void AS
$BODY$
BEGIN
CREATE TEMP SEQUENCE test;
PERFORM testseq1();
DROP SEQUENCE test;
RETURN;
END; $BODY$
LANGUAGE 'plpgsql' VOLATILE;
ALTER FUNCTION testseq() OWNER TO postgres;

CREATE OR REPLACE FUNCTION testseq1()
RETURNS void AS
$BODY$
DECLARE I INTEGER;
BEGIN
I:= nextval('test');
RETURN;
END; $BODY$
LANGUAGE 'plpgsql' VOLATILE;
ALTER FUNCTION testseq1() OWNER TO postgres;

SELECT testseq();

-- this works fine.

SELECT testseq();

ERROR: could not open relation with OID 21152
CONTEXT: PL/pgSQL function "testseq1" line 3 at assignment
SQL statement "SELECT testseq1()"
PL/pgSQL function "testseq" line 3 at perform

Greetings,

Daniel.

try this way:

CREATE OR REPLACE FUNCTION testseq() RETURNS void AS
$BODY$
BEGIN
EXECUTE 'CREATE TEMP SEQUENCE test';
PERFORM testseq1();
DROP SEQUENCE test;
RETURN;
END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
ALTER FUNCTION testseq() OWNER TO postgres;

CREATE OR REPLACE FUNCTION testseq1() RETURNS void AS
$BODY$
DECLARE I INTEGER;
BEGIN
EXECUTE 'select nextval(''test'')' INTO I;
raise notice '%', I;
RETURN;
END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
ALTER FUNCTION testseq1() OWNER TO postgres;

SELECT testseq();
SELECT testseq();

is the same problem as with temp tables, you must put their creation,
and in this case even the nextval in an execute...

--
regards,
Jaime Casanova
(DBA: DataBase Aniquilator ;)

On Tue, Jan 17, 2006 at 01:28:03PM -0500, Jaime Casanova wrote:

is the same problem as with temp tables, you must put their creation,
and in this case even the nextval in an execute...

Curious that it works in 8.0, though. I wonder if the failure in
8.1 is an artifact of changing sequence functions like nextval()
to take a regclass argument (the sequence OID) instead of a text
argument (the sequence name); that would affect what gets put in
the function's cached plan.

--
Michael Fuhr

A nice workaraound because

EXECUTE 'select nextval(''test'')' INTO I;

doesnt work in 8.0 seems to be:

myid:=nextval('stvtrsid_seq'::TEXT);

This seems to work in every case.

Daniel

Jaime Casanova schrieb:

try this way:

CREATE OR REPLACE FUNCTION testseq() RETURNS void AS
$BODY$
BEGIN
EXECUTE 'CREATE TEMP SEQUENCE test';
PERFORM testseq1();
DROP SEQUENCE test;
RETURN;
END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
ALTER FUNCTION testseq() OWNER TO postgres;

CREATE OR REPLACE FUNCTION testseq1() RETURNS void AS
$BODY$
DECLARE I INTEGER;
BEGIN
EXECUTE 'select nextval(''test'')' INTO I;
raise notice '%', I;
RETURN;
END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
ALTER FUNCTION testseq1() OWNER TO postgres;

SELECT testseq();
SELECT testseq();

is the same problem as with temp tables, you must put their creation,
and in this case even the nextval in an execute...

--
regards,
Jaime Casanova
(DBA: DataBase Aniquilator ;)