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Lob Chunk size defaulting to 8192

NeedHelpDBAOct 3 2009 — edited Oct 4 2009
10.2.0.3 Enterprise on Linux x86-64

DB is a warehouse and we truncate and insert and or update 90% of all records daily.

I have a table with almost 8mill records and I ran the below to get max lenght for the lob.

select max(dbms_lob.getlength(C500170300)) as T356_C500170300 from T356 where C500170300 is not null;

The max for the lob was 404 bytes and the chunk size is 8192 and I was thinking that is casuing the lob to have around 50GB of wasted space that is being read during the updates. I tried to creating a duplicate table called T356TMP and lob with 512 and tried 1024 chunk size, both times it changes back to 8192.

I thought it had to be a size that could be multipule or division of the tablespace block size.

Based on what is happening, the smallest chunk size I can make is the tablespace block size, is this a true statement? or am I doing something wrong.

Thanks
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Locked on Nov 1 2009
Added on Oct 3 2009
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