-- 開窗函數：在結果集的基礎上進一步處理(聚合操作)-- Over函數,添加一個字段顯示最大年齡SELECT * ,    MAX(StuAge) OVER ( ) MaxStuAgeFROM  dbo.Student;-- Over函數,添加一個字段顯示總人數SELECT * ,    COUNT(StuID) OVER ( ) StuCountFROM  dbo.Student;-- Partition By 分組統計數量-- 根據性別分組后，統計SELECT COUNT(*) OVER ( PARTITION  BY StuSex ) ,    *FROM  dbo.Student;-- 根據班級分組后，統計、排序SELECT COUNT(*) OVER ( PARTITION  BY Class ORDER BY Height) ,    *FROM  dbo.Student;-- Over函數,添加一個字段顯示平均身高SELECT * ,    AVG(Height) OVER ( ) AgeHeightFROM  dbo.Student;--Row_Rumber()SELECT ROW_NUMBER() OVER ( ORDER BY StuID DESC ) RowNumber ,    *FROM  dbo.Student--Row_Rumber() 實現分頁效果;WITH  T AS ( SELECT  ROW_NUMBER() OVER ( ORDER BY StuID DESC ) RowNumber ,            *        FROM   dbo.Student       )  SELECT *  FROM  T  WHERE  T.RowNumber BETWEEN 1 AND 3;--Rank() 排名函數,名次相同，跳過SELECT RANK() OVER ( ORDER BY Height ) ,    *FROM  dbo.Student;--DENSE_Rank() 排名函數，名次相同不跳過SELECT DENSE_RANK() OVER ( ORDER BY Height ) ,    *FROM  dbo.Student;-- NTILE()函數，參數：記錄總數/劃分區域 = 每個區域數組，把記錄序號放進數組 (平均分組)SELECT NTILE(3) OVER ( ORDER BY StuSex ) ,    *FROM  dbo.Student;