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From: vsevolod afanassiev on 14 Jan 2010 15:54
1. Deleting data: I guess if you want to avoid outage then the only
way is to run DELETE statement.
2. Re-organizing the table: it depends on what you are trying to
achieve. You mention improving performance,
do you have queries that select columns other than VALUE (LOB column)?
Or all queries against this table select
VALUE column? Are LOBs stored inline or nor (view DBA_LOBS column
IN_ROW)? What is average LOB size compared
with block size? In some cases it is preferable to store LOB in the
same block as other columns, in other cases out-of-line
storage is better.
If you don't plan to change LOB storage then it may be sufficient to
delete data, rebuild indexes, and leave table as it is.
From: Frank van Bortel on 19 Jan 2010 14:19
UXDBA wrote:
> All,
>
> Oracle 9.2.0.8
> OS - HP Ux 11.23
>
> We have table T
> count(*) = 31414748
>
> table definition
>
> create table T (
> OBJID NUMBER,
> DEV NUMBER,
> NAME VARCHAR2(20 BYTE),
> VALUE CLOB,
> CONTEXT_INST2GROUP_INST NUMBER,
> CONTEXT_INST2PROC_INST NUMBER
> )
>
[snip!]

Did you specify DISABLE STORAGE IN ROW for the CLOB?
I may help tremendously, if the average LOB size > 4000 byte
--

Regards, Frank van Bortel

Topposting in Usenet groups I regard as offensive - I will not reply
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