ALTER STATEMENT

ü  ‘ALTER ‘ statement is used to change the structure of a table.

ü  It is used to add, modify or delete columns in a table.

ü  To add a column in a table

ü  For add a column in a table we can use following command

Syntax:

ALTER TABLE table1 ADD col_name datatype

Example:

ü  To delete  a column in a table

ü  To delete a column in a table we can use following command

Syntax:

ALTER TABLE table1 DROP COLUMN  col_name

Example:

ü  To  change the  data type of a column in a table

ü  To change datatype of a column in a table we can use following command.

Syntax:

ALTER TABLE table1 ALTER COLUMN  col_name  datatype