Re: Perfomance Help

In article <43d4t9$lt5_at_newsbf02.news.aol.com>,

   diamonds2_at_aol.com (Diamonds2) wrote:
>We had an medium-size Interleaf Application (RDM) that sits on the Oracle
>7.1 system. We are new the Oracle database and need help determining the
>bottlenecks. The database contains less than 200000 records with 2 large
>tables of about 30000 each. Every screen in the RDM application queries
>and
>joins these tables. All the tables were created and are controlled by the
>Interleaf
>Application. What can we do to determine and reduce the bottleneck of the
>
>application.
>
>I was able to do the ANALYZE tbl command on one of the tables and the
>results in the chained row table was 6243. This doesn't sound good. Does
>this
>mean that this table is in bad need of reorganizing??
>
>If I export , do I need to physically issue the DROP Tble command and then
>
>import? Should I export/import on a regular basis??
>
>Thanks for the help,
>
>Felicia

Hi Felicia ! Here are 3 hints :
 your table MUST be reorganized - chained rows are always a perf. bottleneck   (they imply 2 i/o insted of one for each chained rows... Try to figure out   the impact on table-scans...)
 the IMPORT command has no 'replace-like' option : it means that the import   will simply insert your rows in your table (- if you don't drop it, your   primary key or referential constraints may complain...)   -> so drop it before importing your data !!   -> furthermore, it the only way to make a "real" reorg. (rows and extents

     level if you choose the compress option *set by default)

 BEWARE : on 7.1.x, there's a KNOWN BUG related to analyse table (..) before   an export/import : If you have already analyzed your table, issue     "ANALYSE TABLE ... DROP STATISTICS" BEFORE EXPORTING IT, ELSE YOUR IMPORT   COULD FAIL
 (it may happens when the Rdbms tries to reactivate the constraints & index)

 This bug has been fixed since 7.1.6 (perhaps 7.1.5 - don't know).

Bye !   

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