Re: [GENERAL] Doubts about oid

2010-02-19 Thread Vick Khera
On Thu, Feb 18, 2010 at 11:08 PM, Scott Marlowe wrote: > Oracle and postgres are definitely different here.  There's really no > equivalent to rowid in pgsql.  oid has no special optimizations.  An > indexed PK of a serial is about as good as it gets, possibly > clustered. access by CTID is the f

Re: [GENERAL] Doubts about oid

2010-02-19 Thread Alvaro Herrera
Jayadevan M escribió: > I am an Oracle guy who is learning PostgreSQL. oid sounded a lot like > rowid in Oracle. In Oracle, access by rowid is expected to be the fastest > way of accessing a record, faster than even an index access followed by > table access using the primary key. That was why

Re: [GENERAL] Doubts about oid

2010-02-18 Thread Jayadevan M
Hi, > Even in Oracle, I don't believe rowid bypasses > indexes, its more like an implicit SERIAL PRIMARY KEY field. Well, I understand the point is not very relevant, since oid is not similar to rowid. In Oracle, index scans are bypassed if we use rowid. 1)Access by unique index SQL> select *

Re: [GENERAL] Doubts about oid

2010-02-18 Thread John R Pierce
Jayadevan M wrote: Hi, > The primary question that needs to be asked is what do you want to do with them? > It is not so much a performance issue as an admin issue. OIDs where created for > Postgres internal system use and leaked out to user space. As a result they > have some shortcomings as

Re: [GENERAL] Doubts about oid

2010-02-18 Thread Scott Marlowe
On Thu, Feb 18, 2010 at 8:46 PM, Jayadevan M wrote: > > Hi, > > The primary question that needs to be asked is what do you want to do with > > them? > > It is not so much a performance issue as an admin issue. OIDs where created > > for > > Postgres internal system use and leaked out to user spa

Re: [GENERAL] Doubts about oid

2010-02-18 Thread Jayadevan M
Hi, > The primary question that needs to be asked is what do you want to do with them? > It is not so much a performance issue as an admin issue. OIDs where created for > Postgres internal system use and leaked out to user space. As a result they > have some shortcomings as detailed in the ab

Re: [GENERAL] Doubts about oid

2010-02-18 Thread Adrian Klaver
On Wednesday 17 February 2010 8:13:51 pm Jayadevan M wrote: > Hi, > I was reading about oid and default configuration of PostgreSQL. A couple > of doubts > 1) Why is use of OIDS considered deprecated? Is there something else that > can be used in place of oids for user tables? Sequences: http://w