Alter Table SQL

The ALTER TABLE statement is used to add, delete, or modify columns in an existing table. ALTER TABLE also comes under Data Definition language (DDL)

Add Column
Syntax:

                                               ALTER TABLE table_name

                                                ADD column_name datatype

 

 Example

 

                                                ALTER TABLE Customer

                                                ADD Location varchar(50);

 

Drop Column

 Syntax

 

                                             ALTER TABLE table_name

                                             DROP COLUMN column_name

 

 Example

 

                                            ALTER TABLE Customer

                                             Drop Location varchar(50);

 

Change DataType

Syntax

 

                                           ALTER TABLE table_name

                                           ALTER COLUMN column_name datatype

 Example

 

                                            ALTER TABLE Customer

                                            Drop Location varchar(30);