Question

您好，有一种方法可以用更少的时间来应用它，查询现在花费了15分钟太长的时间，并且仍在执行

从[1]的电话中删除（

从[2]中选择电话在'2019-03-04'和'2019-03-22'之间的call_date 联盟
从[3]中选择电话

）开始

Answer 1

我建议：

DELETE one FROM [1] one
WHERE EXISTS (SELECT 1
              FROM [3] three
              WHERE three.phone = one.phone
             ) OR
      EXISTS (SELECT 1
              FROM [2] two
              WHERE one.phone = two.phone AND
                    two.call_date BETWEEN '2019-03-04' AND '2019-03-22'
             );

然后建议在[2](phone, call_date)和[3](phone)上进行索引。

Answer 2

我会尝试将EXISTS与OR一起使用，而不是UNION：

DELETE o 
FROM [1] o
WHERE EXISTS (SELECT 1
              FROM [2] t
              WHERE o.phone = t.phone AND
                    t.call_date >= '2019-03-04' AND t.call_date <= '2019-03-22'
             ) OR
      EXISTS (SELECT 1 FROM [3] tr WHERE tr.phone = o.phone);

如何用更少的时间分配以下内容

2 个答案: