SQL Server 基础：Case两种用法

序言

测试数据

1).等值判断->相当于switch case

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select S#,C#,C#=(     case C#         when 1 then '语文'         when 2 then '数学'         when 3 then '英语'     when 4 then '选修'     end )    from Sc

2)条件判断->相当于if else if else

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select S#,score,score=(     case          when score<60 then '差'          when score between 60 and 80  then '中'          when score between 80 and 90  then '良'      when score between 90 and 100  then '优'      else '缺考'     end )    from Sc

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