Hi Michael,
But what if another insert happens in the mean time? Then the sequence
would have advanced that the data will be scrambled. |Given that this
could be a very active dataset, that situation is almost certain to occur.
Brad
Michael Fuhr wrote:
>On Wed, Sep 22, 2004 at 02:21:42PM +0100, Bradley Kieser wrote:
>
>
>>I have a rule on a view that needs to insert into two tables. The one
>>table has a serial ID as its unique key. The second table links to the
>>first one in one of its columns.
>>
>>I would prefer to keep this as a rule-based solution and not have to
>>write a function as I hope to relicate the solution across many views.
>>
>>I need to either be able to select nextval() the ID for the first table
>>and somehow store this in the rule (but I don't see that rules support
>>variables) or I need to somehow obtain the OID from the first insert in
>>order to select back the ID that was assigned during the insert and pass
>>it to the second insert (trivial to do as the second insert is then
>>simply a select-based insert, provided that I know the OID of that first
>>row!).
>>
>>
>
>The second insert should be able to use currval() to get the current
>value of the sequence used in the first insert. Here's an example:
>
>CREATE RULE v_ins AS ON INSERT TO v DO INSTEAD (
> INSERT INTO a (xxx) VALUES (NEW.xxx);
> INSERT INTO b (col1, col2, col3) VALUES (NEW.col1, NEW.col2, currval('a_id_seq'))
>);
>
>
>
