/**1.Create table guestbook**/
--if object_id('guestbook') is null
--CREATE TABLE guestbook (id int PRIMARY KEY, visitor VARCHAR(40),comments TEXT,entrydate DATETIME)
/**2.Insert data into table guestbook**/
--insert into guestbook values(3,'a','123','2016-05-12')
--insert into guestbook values(4,'a','1234','2016-05-12')
--insert into guestbook values(5,'a','12345','2016-05-12')
/**3.Drop table guestbook**/
--if object_id('guestbook') is not null
--drop table guestbook
--if exists(select * from sysobjects where name='guestbook')
--drop table guestbook
/**4.Update table guestbook**/
--update guestbook set visitor='b' where id='4'
/**5.select all record**/
--select * from guestbook
/**6.Delete data (one record) from table guestbook**/
--delete guestbook where id='3'
/**7.Truncate table guestbook (delete all datas from table guestbook)**/
--truncate table guestbook