Sql e 0 zcount在那里，您只是跳过了它，因为您正在使用q（它是null）作为坐标_id的源，请改用coordst。假设坐标表的大小要小得多，您可以在加入之前先卷起mytable。v在主联接中不是必需的，但它对运行时间的贡献是微不足道的。你只能在q上提高

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e 0 zcount在那里，您只是跳过了它，因为您正在使用q（它是null）作为坐标_id的源，请改用coordst。假设坐标表的大小要小得多，您可以在加入之前先卷起mytable。v在主联接中不是必需的，但它对运行时间的贡献是微不足道的。你只能在q上提高。

WITH v AS (
   SELECT '2012-1-1 11:55:11'::timestamp AS _from -- provide times once
         ,'2012-1-31 22:02:21'::timestamp AS _to
   )
, q AS (
   SELECT c.coordinates_id
        , date_trunc('hour', t.calltime) AS stamp
        , count(*) AS zcount
   FROM   v
   JOIN   mytable t ON  t.calltime BETWEEN v._from AND v._to
                   AND (t.calltime::time >= v._from::time AND
                        t.calltime::time <= v._to::time) AND 
(extract(DOW from t.calltime) = 3)
   JOIN   coordinates c ON (t.lat, t.lon) 
                   BETWEEN (c.bottomrightlat, c.topleftlon)
                       AND (c.topleftlat, c.bottomrightlon)
   GROUP BY c.coordinates_id, date_trunc('hour', t.calltime)
   )
, cal AS (
   SELECT generate_series('2012-1-1 11:00:00'::timestamp
                        , '2012-1-31 23:00:00'::timestamp
                        , '1 hour'::interval) AS stamp)
SELECT q.coordinates_id, cal.stamp::date, sum(q.zcount) AS zcount
FROM   v, cal
LEFT   JOIN q USING (stamp)
WHERE  extract(hour from cal.stamp) BETWEEN extract(hour from v._from)
                                        AND extract(hour from v._to)
AND    extract(DOW from cal.stamp) = 3 
AND    cal.stamp >= v._from
AND    cal.stamp <= v._to
GROUP  BY 1,2
ORDER  BY 1,2;

coordinates_id  | stamp      | zcount
1               ;"2012-01-04";      2
1               ;"2012-01-11";      3
1               ;"2012-01-18";      2
2               ;"2012-01-04";      2
2               ;"2012-01-11";      3
2               ;"2012-01-18";      2

coordinates_id  | stamp      | zcount
1               ;"2012-01-04";      2
1               ;"2012-01-11";      3
1               ;"2012-01-18";      2
1               ;"2012-01-25";      0
2               ;"2012-01-04";      2
2               ;"2012-01-11";      3
2               ;"2012-01-18";      2
2               ;"2012-01-25";      0

WITH v AS (
   SELECT '2012-1-1 11:55:11'::timestamp AS _from -- provide times once
         ,'2012-1-31 22:02:21'::timestamp AS _to
   )
, q AS (
   SELECT c.coordinates_id
        , date_trunc('hour', t.calltime) AS stamp
        , count(*) AS zcount
   FROM   v
   JOIN   mytable t ON  t.calltime BETWEEN v._from AND v._to
                   AND (t.calltime::time >= v._from::time AND
                        t.calltime::time <= v._to::time) AND 
(extract(DOW from t.calltime) = 3)
   JOIN   coordinates c ON (t.lat, t.lon) 
                   BETWEEN (c.bottomrightlat, c.topleftlon)
                       AND (c.topleftlat, c.bottomrightlon)
   GROUP BY c.coordinates_id, date_trunc('hour', t.calltime)
   )
, cal AS (
   SELECT generate_series('2012-1-1 11:00:00'::timestamp
                        , '2012-1-31 23:00:00'::timestamp
                        , '1 hour'::interval) AS stamp)
, coordst AS ( 
   SELECT coordinates_id FROM coordinates)
SELECT q.coordinates_id, cal.stamp::date, COALESCE(sum(q.zcount),0) AS zcount
FROM   v, coordst, cal
LEFT   JOIN q USING (stamp)
WHERE  extract(hour from cal.stamp) BETWEEN extract(hour from v._from)
                                        AND extract(hour from v._to)
AND    extract(DOW from cal.stamp) = 3 
AND    cal.stamp >= v._from
AND    cal.stamp <= v._to
GROUP  BY 1,2
ORDER  BY 1,2;

WITH v AS (
   SELECT '2012-1-1 11:55:11'::timestamp AS _from -- provide times once
         ,'2012-1-31 22:02:21'::timestamp AS _to
   )
, q AS (
   SELECT c.coordinates_id
        , date_trunc('hour', t.calltime) AS stamp
        , count(*) AS zcount
   FROM   v
   JOIN   mytable t ON  t.calltime BETWEEN v._from AND v._to
                   AND (t.calltime::time >= v._from::time AND
                        t.calltime::time <= v._to::time) AND 
(extract(DOW from t.calltime) = 3)
   JOIN   coordinates c ON (t.lat, t.lon) 
                   BETWEEN (c.bottomrightlat, c.topleftlon)
                       AND (c.topleftlat, c.bottomrightlon)
   GROUP BY c.coordinates_id, date_trunc('hour', t.calltime)
   )
, cal AS (
   SELECT generate_series('2012-1-1 11:00:00'::timestamp
                        , '2012-1-31 23:00:00'::timestamp
                        , '1 hour'::interval) AS stamp)
, coordst AS ( 
   SELECT DISTINCT coordinates_id FROM coordinates)
SELECT coordst.coordinates_id, cal.stamp::date, COALESCE(sum(q.zcount),0) AS zcount
FROM   v CROSS JOIN coordst CROSS JOIN cal
LEFT   JOIN q USING q.stamp = cal.stamp AND coordst.coordinates_id = q.coordinates_id
WHERE  extract(hour from cal.stamp) BETWEEN extract(hour from v._from)
                                        AND extract(hour from v._to)
AND    extract(DOW from cal.stamp) = 3 
AND    cal.stamp >= v._from
AND    cal.stamp <= v._to
GROUP  BY 1,2
ORDER  BY 1,2;