Hello Marc,
at first I tried to solve your update of the tables. The example you
gave should be done with an update statement like the following:
update test_table set mygroup=(select t.mygroup from test_table as t where t.family =
test_table.family and t.rang = test_table.rang+1)where rang=0;
If you have to write a function which receives the tablename as an
argument it would look like:
CREATE OR REPLACE FUNCTION test_function(tablename text)
RETURNS integer AS $BODY$BEGIN EXECUTE 'update ' || tablename || ' set mygroup=(select t.mygroup from
'|| tablename || ' as t where t.family = test_table.family and t.rang =
test_table.rang+1)whererang=0;' RETURN 0;END;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;
Generally you should avoid using explicit for/loop constructs in your
stored procedures if the action can be solved by a single SQL
statement, because the optimizer can make a better execution plan.
--
---> Dirk Jagdmann
----> http://cubic.org/~doj
-----> http://llg.cubic.org
