This document discusses Data Control Language (DCL) commands in SQL Server for deleting databases and tables, as well as saving data using save points and rollbacks. It explains that DCL is used to control data and can delete tables using the DROP command or save data using save points and rollbacks with COMMIT, SAVEPOINT, and ROLLBACK commands. Caution is advised when using these commands as changes cannot always be undone.

1. 9SQL SERVER: DELETINGA DATABASE

2. DCL COMMANDSWHAT IS DCL?DATACONTROLLANGUAGEAs the name suggests, DCL is used to control Data. It can be used to save or delete tables or rollback to an existing save point.Save Point: It is a marker that represent a point of integrity in a database transaction. It is more like a backup or a restore point that we use in windows.The Next slide illustrates the Save points concept better.

3. Save Points

4. Deleting tablesDropping of tables:Microsoft SQL Server 2008 provides yet another simple keyword for deleting the table. And that is the word ‘DROP’drop table tablename;The SQL Command drop deletes the table permanently and beyond recovery. Hence, it is advisable to reconsider deletion before performing it.

5. Saving tablesSaving the existing work so that it can be resumed with laterMicrosoft SQL Server 2008 commits to us in this matter by providing us with the keyword ‘COMMIT’commit;Caution: Once used, we cannot undo the changes made to the table previous to this command.

6. Saving tablesUndo-ing the changes done to the table:Microsoft SQL Server 2008 provides a solution with the simple keywords:‘savepoint’ and ‘Rollback’Create a Save pointsavepointsavepointname;Reverts the database state to the most recently created save pointrollback;NOTE: You cannot rollback the DDL commands but only DML commands. So be cautious!!!

7. Summary9. Deletinga database Save Points

8. Dropping tables