Altering a Table: Enhanced Form : ALTER TABLE « Table « SQL Server / T-SQL Tutorial






ALTER TABLE table_name
        [WITH CHECK | NOCHECK]
        ADD col_name type [{NULL | IDENTITY}]
        [{, col_name type NULL | IDENTITY} ...]
        DROP COLUMN col_name [{, col_name} ...]
        ALTER COLUMN col_name type {NULL | IDENTITY}
        [{, col_name type NULL | IDENTITY} ...]
        ADD table_constraint
        DROP table_constraint


16> CREATE TABLE sales
17>         (order_no INTEGER NOT NULL PRIMARY KEY,
18>         order_date DATETIME NOT NULL,
19>         ship_date DATETIME NOT NULL)
20> GO
1>
2> ALTER TABLE sales
3>         ADD CONSTRAINT order_check CHECK(order_date <= ship_date)
4> GO
1>
2> drop table sales;
3> GO








3.2.ALTER TABLE
3.2.1.The basic syntax of the ALTER TABLE statement
3.2.2.drop column syntax
3.2.3.Change the length of the emp_name column in the employee table from varchar(30) to varchar(50)
3.2.4.Alter table to add a constraint based on IN function
3.2.5.Altering a Table: A Basic Form
3.2.6.Alter table to add column
3.2.7.Alter table to drop a column
3.2.8.The DROP COLUMN clause provides the ability to drop an existing column of the table.
3.2.9.ALTER data size for a COLUMN
3.2.10.Altering a Table: Enhanced Form
3.2.11.Use ALTER TABLE statement to define the primary key
3.2.12.Use ALTER TABLE statement to define the foreign key of a table.
3.2.13.Each declarative integrity constraint can be removed using the DROP clause of the ALTER TABLE statement.
3.2.14.Expanded nvarchar(20) to nvarchar(300)
3.2.15.Creating a Computed Column in alter table command
3.2.16.Create a Table Index