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Session 3Implementing and Managing Views ReviewIntroduction to IndexesIndex ArchitectureRetrieving Stored DataFinding RowsVarious Types of IndexesWorking with IndexesViewing Index Information Session ObjectivesIntroduction to ViewsDefining ViewsExploring CREATE VIEW optionsModifying data through Views Introduction to ViewsA view is a virtual table that is made up of selected columns from one ore more tables.A view can include columns from other viewThe data inside the view comes from the base tables that are referenced in the view definition Type of ViewsStandard View: using columns from one or more tablesIndexed View: with a unique clustered indexPartitioned View: a view created using horizontally partitioned data from one or more tables Advantages of viewsSecurity through Personal AccessCustomized Display of DataMerger of Data from Multiple Tables or ViewsOperations on RecordsIntegrity Constraint Checks System ViewsTypes of System Views: Catalog Views Information Schema Views Compatibility Views Replication Views Dynamic Management Views Notification Services Views Creating ViewsSyntax:CREATE VIEW <view_name>AS <select_statement>Sample:CREATE VIEW Salary_Details ASSELECT EmpID, FirstName, LastName, Salary FROM Employee_Details Creating ViewsPermisions to create views:Sysadmin roleDb_ownerDb_ddladminCreate view permisionSelect permission on all tables Alter ViewsA view can be altered by dropping and recreating it or using Alter viewSyntax:ALTER VIEW <view_name>AS <select statement>Sample:ALTER VIEW Salary_Details AS SELECT * FROM Employee_Details WHERE EmpID=1 123doc.vn