worktable understanding and clustered index details

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Adaptive Server Enterprise/15.7.0/EBF 22640 SMP SP52 /P/RS6000/AIX 6.1/ase157sp5x/3293/64-bit/FBO/Tue May 20 21:09:25 2014

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Hi community,

I have a SQL statement based on  derived tables and the first lines of the associated showplan (see attachment).

I'd like to know if it's possible to get some details on the worktable and its clustered index?

Based on the attachment, my understanding is that my worktable1 contains the whole table 'marketDataSet' and it has clustered index on  marketDataSet.M_ALIAS.

Am I correct?

Thanks for your feedback

Simon