How to partition a relation with SQL?

I have a relation that I want to fragment into parts. The naive way to do it would be to load the relation out, partition it and then populate the sub-relations with parts of the original relation.

But, can I issue (perhaps a series of) SQL queries to do it? What if I have a predetermined fragment size ratio that I need to obtain?

Thanks.

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Eddie C. Shek
Hughes Research Laboratories, Los Angeles
shek_at_aic.hrl.hac.com
(310)317-5607