Sorry, I have accidentaly sent incomplet mail.
Here is the rest:
The following sequence of commands will end up with error, because of duplicate ID in table a2:
insert into a2(data2, data) values(456, 'jkl');
insert into a2(data2, data) values(789, 'mno');
Is there any way how to force UPDATE to use default value of ID column from table a2 when updating rows in this table, without using triggers?
Thank you
Best regards
Miroslav Simulcik
2012/2/27 Miroslav Šimulčík
<simulcik.miro@gmail.com>Hi,I have two tables defined for example like this:
create table a1 (id serial primary key, data text);
create table a2 (id serial primary key, data2 integer) inherits (a1);
The point is, that I want to have two tables with inheritance relation between them, but each with its own id column (overriden in child table).
Then I execute this sequence of commands:
insert into a1(data) values('abc');
insert into a2(data2, data) values(123, 'def');
update a1 set id = default, data = 'ghi';
I need new IDs on each update, because I store old rows in another table to keep history of changes. Problem is that update uses values from sequence belonging to table a1 when updating rows in table a2.
So the content of tables after operations is:
select * from only a1;
id | data
----+------
2 | ghi
select * from a2;
id | data | data2
----+------+-------
3 | ghi | 123
The following sequence of commands ends up wit