Alter Table - How to Add a column in a Table and How to Delete a column from a Table

Alter Table - How to Add a column in a Table and How to Delete a column from a Table

The Alter Table statement is used to add, delete or modify the columns of an existing table. Sometimes we need to add a column into an existing table, delete a column from an existing table or modify the structure of the columns like data type, range etc into an existing table then the Alter Table statement is very useful.  

Adding a Column into a Table:-

alter table <table_name> add <column_name datatype>

alter table student_info add (course varchar(30)

Deleting a Column from a Table:-

alter table <table_name> drop <column_name>

alter table student_info drop course

Modify a column into a Table:-


alter table <table_name> modify <column_name datatype>

alter table student_info modify (course varchar(50))

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