Re: my comment earlier today about PostgrSQL databases and row indentification, here's the section of the Rekall manual I remembered:- For some databases, this is always possible. For instance, in PostgreSQL every row has associated with it a unique indeitifier called the oid, which can be retrieved along with the row data; after a new row is inserted, the oid of that row can be ascertained. Similarly, Oracle has a rownum. (... and that indeitifier typo isn't mine!) -- Chris Green (chris@areti.co.uk) "Never ascribe to malice, that which can be explained by incompetence."
On Thu, Nov 11, 2004 at 07:49:53PM +0000, Chris Green wrote:
Re: my comment earlier today about PostgrSQL databases and row indentification, here's the section of the Rekall manual I remembered:-
For some databases, this is always possible. For instance, in PostgreSQL every row has associated with it a unique indeitifier called the oid, which can be retrieved along with the row data; after a new row is inserted, the oid of that row can be ascertained. Similarly, Oracle has a rownum.
(... and that indeitifier typo isn't mine!)
However (ooops!) 'indentification' is my typo! :-) -- Chris Green (chris@areti.co.uk) "Never ascribe to malice, that which can be explained by incompetence."
On 2004-11-11 19:49:53 +0000 Chris Green <chris@areti.co.uk> wrote:
PostgreSQL every row has associated with it a unique indeitifier called the oid, which can be retrieved along with the row data; [...]
Ahhh! I remember this now! I just dug it out of the PostgreSQL manual, which you can find online at http://www.postgresql.org/docs/7.4/static/datatype-oid.html and it explains why using them is discouraged: Also, an OID system column is added to user-created tables (unless WITHOUT OIDS is specified at table creation time). [...] The oid type is currently implemented as an unsigned four-byte integer. Therefore, it is not large enough to provide database-wide uniqueness in large databases, or even in large individual tables. So, using a user-created table's OID column as a primary key is discouraged. [...] Thanks for the reminder that they're there, though! -- MJR/slef My Opinion Only and not of any group I know Creative copyleft computing - http://www.ttllp.co.uk/ Unsolicited attachments to the pipex address deleted Will HLF fund tree-killings? http://www.thewalks.co.uk/
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