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-- Perl Weekly Challenge 165
-- Task 1
CREATE SCHEMA IF NOT EXISTS pwc165;
TRUNCATE points;
INSERT INTO points
VALUES
(53,10, NULL, NULL)
,(53,10,23,30)
,(23,30, NULL, NULL)
;
CREATE OR REPLACE FUNCTION
pwc165.task1_plpgsql()
RETURNS TEXT
AS $CODE$
DECLARE
svg text;
p points%rowtype;
BEGIN
SELECT '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.0//EN" "http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">
<svg height="400" width="400" xmlns="http://www.w3.org/2000/svg" xmlns:svg="http://www.w3.org/2000/svg">'
INTO svg;
FOR p IN SELECT * FROM points LOOP
IF p.x1 IS NOT NULL AND p.y1 IS NOT NULL AND p.x2 IS NOT NULL AND p.y2 IS NOT NULL THEN
-- line
SELECT svg
|| format( '<polyline points="%s %s %s %s" stroke="#ff0000" stroke-width="6" />',
p.x1, p.y1, p.x2, p.y2 )
INTO SVG;
END IF;
IF p.x1 IS NOT NULL AND p.y1 IS NOT NULL THEN
-- point
SELECT svg
|| format( '<circle r="4" cx="%s" cy="%s" stroke-width="0" fill="#000000" />', p.x1, p.y1 )
INTO svg;
END IF;
IF p.x2 IS NOT NULL AND p.y2 IS NOT NULL THEN
-- point
SELECT svg
|| format( '<circle r="4" cx="%s" cy="%s" stroke-width="0" fill="#000000" />', p.x2, p.y2 )
INTO svg;
END IF;
END LOOP;
RETURN svg;
END
$CODE$
LANGUAGE plpgsql;
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