You might try placing the INSERT and SELECT CURRVAL into a transaction
block.-DEJ
> -----Original Message-----
> From: Patrick Welche [SMTP:prlw1@newn.cam.ac.uk]
> Sent: Thursday, April 29, 1999 1:05 PM
> To: pgsql-interfaces@postgreSQL.org
> Subject: [INTERFACES] sequences
>
> After the interesting discussion on what is the safest way to have a
> unique
> "oid"-like value per row, I thought I would have a go, but from libpq++ I
> don't seem to be able to read the new sequence value:
>
> Table = person
> +----------------------------------+----------------------------------+---
> ----+
> | Field | Type |
> Length|
> +----------------------------------+----------------------------------+---
> ----+
> | id | int4 not null default nextval('p |
> 4 |
> | surname | text not null |
> var |
> | firstname | text not null |
> var |
> | email | text |
> var |
> | phone | text |
> var |
> | rfbdate | date |
> 4 |
> +----------------------------------+----------------------------------+---
> ----+
> Index: person_id_key
>
> The output from my test program is:
>
> INSERT INTO person (surname,firstname,email,phone) VALUES
> ('Welche','Patrick','
> prlw1',null)
> SELECT currval('person_id_seq')
>
> Missing person id
>
> and the relevant bit of code is:
>
> query<<"INSERT INTO person (surname,firstname,email,phone) VALUES
> ('"
> <<a._surname<<"','"<<a._firstname<<"',"
> <<ISNULL(a._email)<<','
> <<ISNULL(a._phone)<<')'<<ends;
> s.send_query(query);
> query<<"SELECT currval('person_id_seq')"<<ends;
> s.send_query(query);
> if(s.Tuples()!=1)throw empty_result("Missing person id");
> a.id(toid(s.GetValue(0,"currval")));
>
> send_query prints the query and does a Exec(query). I suppose I don't
> understand the difference between doing things interactively in psql (the
> above INSERT and SELECT work then) and calling things from a program. Any
> tips?
>
> Cheers,
>
> Patrick
