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On 8 Jan 1997 23:19:38 GMT, Nevin Hahn <nhahn_at_ENTENTE.UHCOLORADO.EDU> wrote:
>d941686_at_sp2 (Leong San Io Francisco) wrote:
>>Hello! Happy New Year!
>>
>>Recently, I posted a question regarding extremely bad Oracle performance on
>>Netware, but no one replied... anyway, today, picking up the problem again,
>>I deleted the statistics analyzed from the tables and the server returns
>>back to the same level of performance before. Are statistics really BAD in
>>Oracle 7.2.2? The tables that we have are fairly static so we decided to put
>>on them statistics, but I haven't thought that putting them would be so bad!
>>
>>Francisco Leong
>
>Francisco,
>
>We also observed poor performance with our Oracle 7.2.2 Netware server
>when we were using the optimizer_mode = CHOOSE and analyzing the tables.
>We found that performance increased significantly when we changed the
>optimizer back to RULE. You can still analyze the tables and on a per
>session basis you can turn on the cost based optimizer but the rule
>based optimization works just fine.
>
>Nevin Hahn
>Univ. of Colo. HSC
>
This applies also to 7.3.
Although the manual warns you to specify /* + RULE */, it is sometimes quite helpful. Deleting statistics alone does not seem to help.
--- Rainer Hoerbe / ARGE Netpromote rhoerbe_at_netpromote.co.at ---Received on Mon Jan 20 1997 - 00:00:00 CST