On Fri, Jul 12, 2013 at 1:23 PM, Vincenzo Romano
<vincenzo.romano@notorand.it> wrote:
> Hi all
> I'm making some experiments with table archiving and I'd like to
> "replace" a full table F with an empty one E.
> In order to do this I see only one way:
>
> ALTER TABLE F RENAME TO T;
> ALTER TABLE E RENAME TO F;
> ALTER TABLE T RENAME TO E; -- optional
>
> This implies there's a moment when the full table doesn't exist.
> Would a transaction enclosure ensure that the table F will be always
> available to all clients?
If I get it right using transaction boundaries around the DDL will
prevent clients to query the F table until the transaction ends, and
this is due to the locking of the alter table. In other words, a query
performed against the F table while the transaction is running will
simply locks without generating any error.
Hope this helps.
Luca