Re: [GENERAL] Questions regarding OID

Hi,

On Fri, 25 Jun 1999, Karl DeBisschop wrote:

|o| >   3) How does one INSERT data in a table with an oid field? (what does one
|o| >   put in the VALUES () entry assigned to the OID?)
|o|
|o| We've never tried to INSERT with a predetermined OID, and I'm
|o| pretty sure it would break things if you tried.  What happens is
|o| that a free OID is assigned, which you can then look up.  The last
|o| OID assigned is generally shown by psql.  PHP and perl's DBD::Pg
|o| provide methods for accessing the last OID after an INSERT.  You
|o| can then write this value into another table.

I'm sorry. What I meant was, given a the ff. definition of a table:

CREATE TABLE foo
 (
  id    oid,
  ...
 );

how does one INSERT data into that table? Should I do

INSERT INTO foo VALUES (???, ...);

|o| >   4) What happens if you CREATE a table with more than one field with oids?
|o|
|o| Let's be precise here.  There is an OID for each row in the
|o| database, but there is also an oid datatype.  By definition, you
|o| cannot have more than one OID for a given row.  But you may have
|o| an arbitrary number of fields in a table that have oid types.
|o| These fields would typically point to other rows in other tables.

I think I seem to have misunderstood OIDs. So there's an oid datatype, and
there's an associated OID for every record. Hmmm ... dunno how that helps
me. What I really want is simple: I wish to assign a unique ID for each
record. I was hoping OIDs would by my solution because otherwise I'd have
to use a numeric idea increasing each by one for every INSERT. That would
require that I look for the MAX() ID value and increment that before
INSERTing. Then there's the problem of DELETEing records which would leave
blanks in my ID sequence.

I just assumed that by adding an oid datatype, it'd be assigned a unique
idea at every INSERT.

So is the OID guaranteed to never change?

|o| You're welcome.  But remeber, this is a rather limited sort of
|o| help.

Well, this is the best explanation I've seen so far. Thank you again.


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