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Re: NEWBIE: How do I get the oldest date contained in 3 tables

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Tom Lane wrote:
"Dann Corbit" <DCorbit@xxxxxxxxx> writes:
owner@xxxxxxxxxxxxxx] On Behalf Of Lorenzo Thurman
I have three tables using date fields. I want to retrieve the oldest
date contained in the tables. Can someone show me an example of a query
that would do that?

Just do a union and return the min

That's probably not enough detail for a newbie ...

SELECT min(x) FROM
(
 SELECT min(datecol1) AS x FROM table1
 UNION ALL
 SELECT min(datecol2) AS x FROM table2
 UNION ALL
 SELECT min(datecol3) AS x FROM table3
) ss;

Exercise for newbie: which of the AS clauses are redundant?

			regards, tom lane

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Um, all of them?


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