Thomas wrote:
> Hi,
>
> I have a great performance problem on an Oracle 9.2.0.1 Server...
> (This Problem is independent from the version)
> I try to update a table containing about 800,000 Rows with the
> following statement:
>
> UPDATE ACCT_RELATION SET GETSCORE=1
> WHERE mandant||kndid||ktoid IN (
> SELECT mandant||kndid||ktoid
> FROM ACCOUNT) ;
>
> Only Four rows but about two days of processing time. This is not the
> only statetement used, so the complete job would sum to about 10 days
> of processing time. This is much, much too long.
> Has anyone an Idea how to speed up the processing by changing the
> statement?
>
> more information:
> both tables ACCT_RELATION and ACCOUNT have about 800000 rows.
> no index
> no primary defined
> mandant,kndid,ktoid is a unique tuple.
> Would an index help or does oracle make a tablescan even if the index
> exists?
Also perhaps worth mentioning is that this type of approach ("where
col1||col2||col3 = something") may not always give the correct results,
because 12 || 345 || 6 is the same as 1 || 23 || 456.
Received on Mon Dec 12 2005 - 18:12:37 CST
