prepare, execute & oids

On Tue, Aug 01, 2006 at 06:19:29PM +0200, phazon wrote:

I juste want to get the OID of the line inserted. Does anyone know how to do
it ?

It depends on the client interface. What interface are you using?

OIDs are deprecated as row identifiers; the preferred method is to
use a sequence (serial column). To get a sequence's value you can
use currval() or lastval() (the latter available in 8.1).

--
Michael Fuhr

I use PHP.
When I make juste a simple insert like

Insert Into my_table (my_field) values ('value')

I get back the OID of the inserted line.

But when i use the prepareInsert fonction, I get nothing back. That's a
pprobleme becaus i need to take the primary key of the line inserted in
order to make post-operations.

I can't use the curval of a sequence because it can be the value of another
insert made by another user.

I use a prepare function because it's really faster (I need to insert many
entries, nearly 5000) and i look for any way to make it faster and get the
primary key of all the line inserted.

2006/8/1, Michael Fuhr <mike@fuhr.org>:

On Wed, Aug 02, 2006 at 09:25:43AM +0200, phazon wrote:

When I make juste a simple insert like

Insert Into my_table (my_field) values ('value')

I get back the OID of the inserted line.

You really don't want to use OID, you want a sequence. (Hint: OIDs are
not really unique, not a primary key).

I can't use the curval of a sequence because it can be the value of another
insert made by another user.

currval() is the last value in *your current session*. It won't be
affected by other users.

Have a nice day,
--
Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/

phazon wrote:

I use PHP.
When I make juste a simple insert like

Insert Into my_table (my_field) values ('value')

I get back the OID of the inserted line.

But when i use the prepareInsert fonction, I get nothing back. That's a
pprobleme becaus i need to take the primary key of the line inserted in
order to make post-operations.

I can't use the curval of a sequence because it can be the value of
another insert made by another user.

currval is transaction safe, it's not a problem you need to worry about.

http://www.postgresql.org/docs/8.1/static/functions-sequence.html

--
Postgresql & php tutorials
http://www.designmagick.com/

On Wed, Aug 02, 2006 at 09:25:43AM +0200, phazon wrote:

I use PHP.
When I make juste a simple insert like

Insert Into my_table (my_field) values ('value')

I get back the OID of the inserted line.

But when i use the prepareInsert fonction, I get nothing back. That's a
pprobleme becaus i need to take the primary key of the line inserted in
order to make post-operations.

The PHP source code has no prepareInsert function -- are you using
a third-party module? If so then try contacting that module's
maintainer. But as I mentioned previously and as Martijn pointed
out, OIDs aren't suitable as primary keys. See the documentation
and FAQ:

http://www.postgresql.org/docs/8.1/interactive/datatype-oid.html
http://www.postgresql.org/docs/faqs.FAQ.html#item4.12

I can't use the curval of a sequence because it can be the value of another
insert made by another user.

As Martijn and Chris mentioned, currval() is safe in this respect.
Its behavior is documented and is the subject of an FAQ item:

http://www.postgresql.org/docs/8.1/interactive/functions-sequence.html
http://www.postgresql.org/docs/faqs.FAQ.html#item4.11.3

--
Michael Fuhr