Boolean Logic in Select Statement

This question already has an answer here:

How do I perform an IF…THEN in an SQL SELECT? 22 answers

How do I return a boolean value from a query during condition evaluation? 4 answers

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SELECT t.[Key]
      ,t.[Parent_Key]
      ,t.[Parent_Code]
      ,t.[Code]
      ,t.[Desc] 
      ,t.[Point]
      ,CASE WHEN t.[Point] > 2 THEN 1 ELSE  
            CASE WHEN t.[Point] = 1 THEN 0 ELSE NULL END 
       END AS [isChild]
      ,t.[By] 
      ,t.[On]
FROM [db].[stats] t WHERE t.[Parent_Key]= @tmpParameter

请注意，当t [Point] <1时，[isChild]将为空

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凯斯是你的朋友...

 SELECT Key, Parent_Key, Parent_Code, Code, Desc, point, 
     case when point > 2 then 1 
          when point = 1 then 0 end isChild, 
     [By], [On]
 FROM db.stats  
 WHERE Parent_Key= @tmpParameter

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使用case语句：

SELECT t.[Key]
      ,t.[Parent_Key]
      ,t.[Parent_Code]
      ,t.[Code]
      ,t.[Desc] 
      ,t.[Point]
      ,CASE t.[Point] WHEN 1 THEN FALSE WHEN 2 THEN TRUE END as [isChild]
      ,t.[By] 
      ,t.[On]
FROM [db].[stats] t WHERE t.[Parent_Key]= @tmpParameter

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