From: Jan Steinman
Date: October 3 2012 11:08pm
Subject: Accessing Column Aliases In Other Columns?
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I would like to refer to calculated columns in other columns. I thought =
a column alias would do it, but apparently they're only for aggregation, =
like GROUP BY.

Other than repeating the entire calculation, what techniques are =
available for accessing such a calculation?

I'm calculating an electric bill, based on meter readings. I need to =
subtract two meter readings, and use that number in several other =
calculations, for example.

----------------
:::: Transformation is not what happens once we've "changed"; it's =
coming out of the dark and seeing what we've got and relating to it =
appropriately and clearly. If we've got a funnel in our hands but we =
think it's a bucket, we're going to keep losing things we value. If we =
know we've got a funnel, then we stick one finger in the hole and use it =
like a bucket to get by in the absence of one. We're "transformed" when =
we fully know who we are =97 or, even more important, who we are not. -- =
Rick Lewis
:::: Jan Steinman, EcoReality Co-op ::::