Re: [NOVICE] OID Question

#1

On Thu, Nov 11, 2004 at 03:34:14PM -0500, Geoffrey wrote:

Quote:

So this prompts a question regarding the documentation. I'm assuming
that I can address the wrap-around issue based on the following found
under "Notes" section of the "Create Table" document:

"Whenever an application makes use of OIDs to identify specific rows of
a table, it is recommended to create a unique constraint on the oid
column of that table, to ensure that OIDs in the table will indeed
uniquely identify rows even after counter wraparound."

Am I reading this correctly? If I place a unique constraint on the oid
column, I will not have to worry about oid wrap around?

Nope, it means that OIDs are not inherintly unique and you need to make
an index to force them to be unique. The OID counter will still
wraparound but now if the OID is reused your INSERT will just fail
instead of inserting a duplicate.

Seriously, use a SERIAL, OIDs are nowhere near as interesting as people
keep suggesting...
--
Martijn van Oosterhout <kleptog (AT) svana (DOT) org> http://svana.org/kleptog/

Quote:

Patent. n. Genius is 5% inspiration and 95% perspiration. A patent is a
tool for doing 5% of the work and then sitting around waiting for someone
else to do the other 95% so you can sue them.

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#2

At 03:34 PM 11/11/04, Geoffrey wrote:

Quote:

Bruno Wolff III wrote:
On Thu, Nov 11, 2004 at 10:04:30 -0500, Terry Lee Tucker
terry (AT) esc1 (DOT) com> wrote:

Greetings,
Here is a simple question:
Is it ok to put a unique index on the oid for my tables? We are in
the process

Yes, but you may occasionally have insert failures if the oid wraps
around and you try to reuse one on an insert.

So this prompts a question regarding the documentation. I'm assuming that
I can address the wrap-around issue based on the following found under
"Notes" section of the "Create Table" document:

"Whenever an application makes use of OIDs to identify specific rows of a
table, it is recommended to create a unique constraint on the oid column
of that table, to ensure that OIDs in the table will indeed uniquely
identify rows even after counter wraparound."

Am I reading this correctly? If I place a unique constraint on the oid
column, I will not have to worry about oid wrap around?

Wrong. Wrap around by itself is not the problem here. When wrap around
occurs, it will be possible to have two rows with the same oid. The
"unique contraint" will prevent duplicate oid's in the table.

Frank

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Re: [NOVICE] OID Question

comp.databases.postgresql.general comp.databases.postgresql.general

Re: [NOVICE] OID Question - 11-11-2004 , 02:42 PM

Re: [NOVICE] OID Question - 11-11-2004 , 04:00 PM