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Mon, 04 Mar 2013 19:15:32 -0800 (PST)
 04 Mar 2013 19:15:32 -0800 (PST)
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Date: Mon, 4 Mar 2013 19:15:31 -0800 (PST)
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Subject: What query could I use to draw a support line on a stock chart?
From: Nick <nboutelier@gmail.com>
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To: pgsql-general@postgresql.org

Using this basic chart as an example, how could I write a query that would give me the lowest points of a trendline?

chart = http://nboutelier.s3.amazonaws.com/images/support_line.png

Here's the data
INSERT INTO data (date,price) VALUES (0,3);
INSERT INTO data (date,price) VALUES (1,4);
INSERT INTO data (date,price) VALUES (2,2);
INSERT INTO data (date,price) VALUES (3,7);
INSERT INTO data (date,price) VALUES (4,3);
INSERT INTO data (date,price) VALUES (5,8);
INSERT INTO data (date,price) VALUES (6,3);
INSERT INTO data (date,price) VALUES (7,6);
INSERT INTO data (date,price) VALUES (8,4);
INSERT INTO data (date,price) VALUES (9,9);
INSERT INTO data (date,price) VALUES (10,4);
INSERT INTO data (date,price) VALUES (11,6);

The query would return the results
10 | 4
 6 | 3
 2 | 2