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SQLSERVER_9: Insert, Delete and Update Command

SQLSERVER_9: Insert, Delete and Update Command

Insert, Delete and Update commands are the Data Manipulation Commands in SQL Server.

a.     Insert

Insert command is used to create new records / rows in the Table. The following command is a basic example of Insert Command.

Ø  Insert into Emp(Empno, Ename) values (101,'ABC')

The above command inserts into table named “Emp” and in columns “Empno”, “Ename” with values 101 and ABC.

The above command has following advantages:

a.      We can skip any column in which we don’t want to insert any data.
b.     We can also change the order of columns.

The another type of insert command:

Ø  Insert into Emp values (101,'ABC')

In the above command, we cannot change the Column Order and even we can’t skip any column value.

b.     Update

Update command is used to update existing values within the table.

Ø  Update Emp set Ename='New Name' where Empno = 101

In the above command we are trying to change the column name Ename to a new Value where Empno = 101

Ø  Update Emp set Ename='New Name', salary=Salary+100 where Empno = 101

In the above command we are trying to change the column name Ename to a new Value, increase salary with already salary + 100 where Empno = 101
c.      Delete

Delete command is used to remove a row or number of rows in a table.

Ø  Delete From Emp where Empno = 101

The above command will be used to delete row from the table where Empno = 101

Ø  Delete From Emp where Salary between 2000 and 10000

The above command will delete all the rows that have salary between 2000 and 10000. Be-Aware as it will delete a number of rows.

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