Monthly Archives: November 2010

Alternate Method For Sequences

So if you’ve used Netezza sequences you may have noticed they are all over the place, and far from sequential.  This is just the nature of a share nothing massively parallel architecture.  But if you want sequential sequences that automatically … Continue reading

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Rownum In Netezza?

Those of you coming from the Oracle world may find you are missing a ROWNUM pseudo column in Netezza.  Sure there’s the LIMIT clause, but sometimes you have a need to assign a sequential number to each row.  The best solution … Continue reading

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Make Your Sequences 25 Times Faster

So where I work we have the need to sequence a few hundred million rows a day.  Surprisingly using a Netezza sequence object took about 2 hours on a 10200 to sequence 70 million rows.  This was acceptable for our initial … Continue reading

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With Netezza Always Use Integer Join Keys For Good Compression, Zone Maps, And Joins

So I’ll start off with a real simple best practice.  Make sure your join keys are integers.  First off this will mean, if you don’t already, you’ll want to use surrogate keys in your physical table model.  First, integers and … Continue reading

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