Question

需要有关查询算术计算的帮助

我想计算特定期限内预订的平均入住率。我正在尝试的是（总家庭数）/（预订总数）和列应分组

第一个查询在下面给我

Total Family
2
3
1
1
1
3

和第二个给了我3，但完整的查询仍然给我与第一个查询相同的结果，即使我将第二个查询替换为＆＃39; 3＆＃39;

Total Family
2
3
1
1
1
3

尝试此查询：

SELECT COUNT( familymember.id ) AS 'Total Family'
FROM familymember,
  reservation
WHERE familymember.fid = reservation.patientId
GROUP BY reservation.patientId/
  (SELECT COUNT( reservation.id )
  FROM reservation
  WHERE reservation.checkout <> '0000-00-00'
  AND reservation.checkin BETWEEN '2014-04-01' AND '2014-04-30'
  )

测试此查询

SELECT COUNT( familymember.id ) AS 'Total Family'
FROM familymember,
  reservation
WHERE familymember.fid = reservation.patientId
GROUP BY reservation.patientId /3

如果你对此有所帮助，我真的很感激。

由于

sql计算期间的平均预订占用率

0 个答案: