ckjianzhong7
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大佬看看这条 sql 语句怎么优化

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  •   ckjianzhong7 · Mar 30, 2019 · 2397 views
    This topic created in 2778 days ago, the information mentioned may be changed or developed.

    SELECT count(traffic_id) FROM traffic WHERE traffic_enterTime >= date_sub(curdate(),interval 1 day) AND traffic_enterTime <= date_sub(curdate(),interval 0 day) UNION SELECT count(DISTINCT traffic_ip) FROM (SELECT * FROM traffic WHERE traffic_enterTime >= date_sub(curdate(),interval 1 day) AND traffic_enterTime <= date_sub(curdate(),interval 0 day)) as subfrom;

    5 replies  •  2019-03-31 14:22:32 +08:00
    ckjianzhong7
    ckjianzhong7
    OP
    Mar 30, 2019
    1
    SELECT count(traffic_id) FROM traffic WHERE traffic_enterTime >= date_sub(curdate(),interval 1 day) AND traffic_enterTime <= date_sub(curdate(),interval 0 day) UNION SELECT count(DISTINCT traffic_ip) FROM traffic WHERE traffic_enterTime >= date_sub(curdate(),interval 1 day) AND traffic_enterTime <= date_sub(curdate(),interval 0 day);
    des
    des
    Mar 30, 2019
    2
    数据结构没有,有没有索引,数据量,EXPLAIN 都没有,你想怎么优化?
    在 traffic_enterTime 加个索引先?
    murmur
    murmur
    Mar 30, 2019
    3
    没有 explain 你让我们对着你的帖子 explain 么
    程序员也不是神啊
    GGGG430
    GGGG430
    Mar 30, 2019 via iPhone
    4
    拆分为多个子 sql,不要在 sql 里用函数
    gosleep
    gosleep
    Mar 31, 2019 via iPhone
    5
    看过优化好像用 explain 返回的结果可以获取行数,搜一下…
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