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Message Posted: Mon, 15 Sep 2003 @ 05:52:28 GMT

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What you are seeing as part of the currentperm retrieved from DBC.TABLESIZE is in terms of the datablocksize(ie. a multiple of the datablocksize).

You would have to consider the table header datablocks that are distributed on all the amps. You would also have to consider whether you table is fallback or not.

The sum(col lengths) would work fine if all the fields were fixed length fields.

So the calculation for a base table size could look like :

Tbl header datablocksize * number of Amps = A
Sum(col lengths)* number of rows                = B{Assuming fixed len flds)
                B*2(if fallback)                        = C
Base Table Size                                         = A+B+C

If you were to have Secndary,Join,Reference,Hash indexes than again you need to consider space associated with these subtables also.

So all these put together is what you see as part of the currentperm from DBC.TABLESIZE.

Narayan.

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