SQL Server.第四章

/*----------------------------------------索引-----------------------------------------------------*/
   /*--聚集索引--*/
       --主键会自动生成同名聚集索引，不能再创建

   /*--非聚集索引--*/
       --基本语法
           --CREATE [ UNIQUE ] [ CLUSTERED | NONCLUSTERED ]
           --INDEX   index_name
           --ON table_name (column_name)
           --[WITH FILLFACTOR=x] 填充因子：指定一个0～100之间的值，表示索引页填充的百分比

       --创建索引
           --如果存在该索引，先将其删除掉
           IF exists(SELECT * FROM sys.indexes WHERE name = 'IX_score')
               DROP INDEX stuMarks.IX_score
           --对成绩字段创建非聚集索引，填充因子30%
           CREATE NONCLUSTERED INDEX IX_score ON stuMarks(score) WITH FILLFACTOR= 30
           GO

       --使用索引
           --指定按索引查询
           SELECT * FROM stuMarks WITH(INDEX = IX_score)
           WHERE score between 60 and 90

/*----------------------------------------视图-----------------------------------------------------*/
   select * from stuinfo where stusex = '男'
   --基本语法
       --CREATE VIEW view_name [(列名...)]
       --AS
       --<SELECT语句>

   --创建视图
       --如果存在该视图，先将其删除掉
       IF EXISTS (   SELECT * FROM sys.views WHERE NAME = 'view_stuInfo_stuMarks')
           DROP VIEW view_stuInfo_stuMarks
       GO
       --创建名为view_stuInfo_stuMarks的视图
       CREATE VIEW view_stuInfo_stuMarks(学号,姓名,成绩)
       AS
           SELECT stuName,stuInfo.StuID,score FROM stuInfo LEFT JOIN stuMarks
           ON stuInfo.StuID = stuMarks.StuID
       GO

   --使用视图
       select * from view_stuInfo_stuMarks

   --视图加密
       --查看所有视图信息
       select * from information_schema.views;
       EXEC sp_helptext 'view_stuInfo_stuMarks'
       --加密试图
       IF EXISTS (   SELECT * FROM sys.views WHERE NAME = 'view_stuInfo_stuMarks')
           DROP VIEW view_stuInfo_stuMarks
       GO
       CREATE VIEW view_stuInfo_stuMarks(学号,姓名,成绩)
       WITH encryption
       AS
           SELECT stuName,stuInfo.StuID,score FROM stuInfo LEFT JOIN stuMarks
           ON stuInfo.StuID=stuMarks.StuID
       GO

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