Re: References to SERIAL

"Brett W. McCoy" wrote: >On Sat, 30 Dec 2000, Thomas SMETS wrote: > >> If i create a "internal pk" buy defining on a
tablea field SERIAL. >> How do I reference this field in the other table to set the field >> possible value ?... > >You
meanas a foreign key?  You would do something like > >create table books_authors ( >    book integer references
book(book_pk)>        on delete no action,...
 

If you need to know which value was used for the SERIAL field, there are
two ways:

1. Use currval('book_book_pk_seq')  to get the last value used in this
session.


bray=# insert into junk (name) values ('Fred');
INSERT 1780993 1
bray=# select currval('junk_id_seq');currval 
---------      1
(1 row)

2. Use the OID which is returned by a successful INSERT statement to look
up the newly-created row from the table:


bray=# insert into junk (name) values ('Fred');
INSERT 1780993 1
bray=# select * from junk where oid = 1780993 ;id | name 
----+------ 1 | Fred
(1 row)


-- 
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight                              http://www.lfix.co.uk/oliver
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