| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
 |
 | |||
| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
|
| |||
Home -> Community -> Usenet -> c.d.o.server -> Re: URGENT!! Limit on Number of tables
A copy of this was sent to rtallak_at_ems.att.com
(if that email address didn't require changing)
On Wed, 16 Jun 1999 15:01:26 GMT, you wrote:
>Hi All,
>
>Is there a limit on the number of tables that can be joined in Oracle
>8i in a SELECT query? I read that there is a 16 table limit on joins is
>it true for Oracle 8i? URGENT!!
no -- there never has been a limit on the number of tables in a join in Oracle. I've done (as a test) upwards of 300 tables in a single statement.
>
>In general, is there any performance drop when the number of tables
>joined is large (like > 10)?
>
the optimizer might take longer (more plans to consider)
the performance of such a query might be slower then if you denormalized, however maintaining the denormalized data might be slower then keeping all of the pieces separate (that is -- your mileage may vary, depends on what you are doing)
>Thanx in advance,.
>RTallak
>
>
>Sent via Deja.com http://www.deja.com/
>Share what you know. Learn what you don't.
See http://www.oracle.com/ideveloper/ for my column 'Digging-in to Oracle8i'... Mirrored (and more current) at http://govt.us.oracle.com/~tkyte/
Current article is "Fine Grained Access Control", added June 8'th
Thomas Kyte tkyte_at_us.oracle.com Oracle Service Industries Reston, VA USA--
 |
 |