小编Chr*_*ing的帖子

我需要在同一个表中查找可能匹配的客户记录。逻辑如下。然而，这似乎在 O(N²) 下执行。有没有办法提高这里的性能？我试过设置索引、散列列并进行比较等，但在大型数据集上的性能仍然很糟糕。我还在下面添加了查询计划。

SELECT
    C1.CustomerId AS Customer1, 
    C2.CustomerId AS Customer2
FROM Customer C1
INNER JOIN Customer C2
    ON 
    C1.CustomerId != C2.CustomerId
    AND
    (C1.FirstName = C2.FirstName OR C1.BirthDate = C2.BirthDate)
    AND
    (
        C1.EmailAddress = C2.EmailAddress
        OR
        C1.MobilePhoneNumber = C2.MobilePhoneNumber
        OR
        (
            C1.HomeAddressLine1 = C2.HomeAddressLine1
            AND
            (
                C1.HomePostCode = C2.HomePostCode
                OR
                C1.HomeSuburb = C2.HomeSuburb
            )
        )
    )