sql-server - 寻找 SQL Server 查询优化

Question

我有这个在 SQL Server 中运行非常慢的查询。请建议对其进行优化以更快地运行。

• TABLE_A有 100'000'000 行
• TABLE_B有 1'000'000 行

ID两个表在,Modify_Date和Source列上都有非聚集索引。

询问：

Insert into TABLE_A       
  select * from RABLE_B B
  Where NOT Exists (Select 1 
                    From TABLE_A A
                    Where B.ID = A.ID
                      And B.Modify_Date = A.Modify_Date
                      And B.Source = A.Source)

Answer 1

INSERT  INTO TABLE_A
        SELECT  B.*
        FROM    TABLE_B B
                LEFT JOIN TABLE_A A ON B.ID = A.ID
                                   AND B.Modify_Date = A.Modify_Date
                                   AND B.Source = A.Source
        WHERE   A.ID IS NULL