Re: Oracle Slower than Access?

In article <3613b18c.163476386_at_news.leading.net>, Joe Brown <joebrown> wrote:

>3. Rollback segments. Oracle has them, I don't believe Access does.
>
>When you send a transaction to Oracle, instead of actually storing the
>data in the tablespace, it holds it into a rollback segment. Once the
>transaction is commited, the data is then moved from the rollback
>segment to the actual table.

This isn't quite correct. The rollback segments hold the _old_ data, not the data that's been updated. On a commit, the data in the relevant tablespace is marked as current, and the rollback segment is released. On a rollback, the rollback segment is used to remove the new data and reconstruct the old data.

Actually, this closes in a couple of other issues in this sort of Oracle/Access comparison. One is, how would Access perform if there were several clients accessing the database simultaneously? The second, what happens if you kill the Access process in the middle of the update? In the first case, all things being equal, Access won't perform nearly as well as Oracle. In the second case, you may possibly have to kiss your database goodbye. Received on Thu Oct 01 1998 - 15:08:11 CDT