Onece丶 2017-07-19 06:21 采纳率: 0%
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求大神帮忙优化下saql,在线等

SELECT
SN,
IP,
sum(IF(type = 1, count, 0)) AS BS_COUNT,
sum(IF(type = 2, count, 0)) AS BS_EXT_COUNT
FROM
(
SELECT
c.SN,
c.IP,
COUNT(b.FN_SN) count,
1 AS TYPE
FROM
cc c
LEFT JOIN runtime_station b ON c.SID = b.CC_SID
WHERE
c.SN = 201705110003
GROUP BY
c.SN,
c.IP
UNION
SELECT
d.SN,
d.IP,
COUNT(r.SN) count,
2 AS TYPE
FROM
cc d
LEFT JOIN base_radar r ON d.SID = r.CC_SID
WHERE
d.SN = 201705110003
GROUP BY
d.SN,
d.IP
) ccinfo
GROUP BY
SN,
IP

  • 写回答

1条回答 默认 最新

  • bibi12526 2017-07-19 07:32
    关注

    减少函数使用,减少连表查询

    评论

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