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Subject: Reuse previously calculated column in sql query?
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Date: Wed, 20 Oct 2004 14:50:11 +0200
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Thread-Topic: Reuse previously calculated column in sql query?
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From: "Philippe Lang" <philippe.lang@attiksystem.ch>
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Hello,

Is it possible to reuse a previously calculated column in a following
column, like:

SELECT
foo.val1 AS col1,
long_calculation(foo.val1) AS col2,
COL2 * 0.75 AS col3
FROM foo;

instead of writing:

SELECT
foo.val1 AS col1,
long_calculation(foo.val1) AS col2,
long_calculation(foo.val1) * 0.75 AS col3
FROM foo;


Philippe