sql-server - 将一个表的数据与另一个表的数据进行比较的最佳方法是什么？

Question

我有 2 个选择语句:

SELECT DISTINCT Email
FROM         dbo.Customers
WHERE     (Email IS NOT NULL) 
AND (Email LIKE '%@%') 
AND (RIGHT(Email, 4) IN ('.net', '.com', '.org')) 
AND (Email NOT LIKE '%@UniformCity.com') 
AND (Email NOT LIKE '%@LifeUniform.com') 
AND (CHARINDEX('.',Email) <> 1)
AND (RIGHT(RTRIM(Email), 1) <> '.') AND (LEFT(LTRIM(Email), 1) <> '@') 
AND (Email not Like '%[`:;_*-,^[^]()+%\/=#-]%' escape '^') order by Email

和

SELECT  replace(replace(
replace(
replace(EmailOptOut,'"','')
, ',held','')
, ',unsub','')
, ',confirm','') 
as CleanEmail
FROM [LifeMail].[dbo].[EmailOptOuts]

我只想从 Customers 表中选择电子邮件，它们不在 EmailOptOuts 表中。实现这一目标的最佳方法是什么？我考虑过使用游标和循环......

Answer 1

我打算将这些表放入临时表中，但如果需要，您可以组合查询。

SELECT DISTINCT Email
INTO    #tCustomersEmail
FROM    dbo.Customers
WHERE   ( Email IS NOT NULL )
    AND ( Email LIKE '%@%' )
    AND ( RIGHT(Email, 4) IN ( '.net', '.com', '.org' ) )
    AND ( Email NOT LIKE '%@UniformCity.com' )
    AND ( Email NOT LIKE '%@LifeUniform.com' )
    AND ( CHARINDEX('.', Email) <> 1 )
    AND ( RIGHT(RTRIM(Email), 1) <> '.' )
    AND ( LEFT(LTRIM(Email), 1) <> '@' )
    AND ( Email NOT LIKE '%[`:;_*-,^[^]()+%\/=#-]%' ESCAPE '^' )
ORDER BY Email

SELECT  REPLACE(REPLACE(REPLACE(REPLACE(EmailOptOut, '"', ''), ',held', ''),',unsub', ''), ',confirm', '') AS CleanEmail
INTO #tOptOuts
FROM    [LifeMail].[dbo].[EmailOptOuts]

SELECT Email
FROM #tCustomersEmail AS tce
WHERE Email NOT IN (SELECT CleanEmail FROM #tOptOuts AS too)