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Message Posted: Wed, 10 Sep 2003 @ 06:35:14 GMT

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The difference is due to differing amounts of unused space at the end of blocks and the number of blocks required for each table.

Teradata has a logical file system comprised of variable length blocks composed of multiples of 512 byte sectors

With maintenance on a table, block splits etc happen. Typically, if you take an old table and then create a clone and insert select into it, the new table will tend to have more larger blocks with less total unused space in them.

You can verify this via Ferret I think.

Over time, the two tables will tend to apporach the same size in physical space but there is no guarantee that they will ever be exactly the same.

I'm not sure about Arcmain copy but probably still susceptible to what blocks happen to avaiable in the freeblock lists of the cylinders used for each table as it is built.

Regards

Andy Baker

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