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From Dag.Wan...@Sun.COM (Dag H. Wanvik)
Subject Re: Storing length information for CLOB on disk
Date Thu, 28 Aug 2008 22:29:34 GMT

Thanks for the overview of this issue, Kristian. I agree this looks
like something we need to address; LOBs are much used and good
performance here is important. 

Kristian Waagan <Kristian.Waagan@Sun.COM> writes:
> I'm bringing up b) because JDBC has methods for inserting data without
> specifying the length. Throwing out some ideas:
>  - obtain required information on the fly, update immediately after
> insert is done

This seems the obvious choice; what is the downside, if any, to this
option? 

Storing both lengths seems cheap enough for large LOBs; if we worry this is
an issue for smaller LOBs, I guess we could encode the ints, so short
lengths take little space..

>  - insert data without length information, then
>     * update on first subsequent request
>     * use a background task to update information
>     * add a "maintenance routine" for updating the information

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