Changing column properties

Use the ALTER TABLE statement to change column properties, such as nullability, LOB options, scope, constraints and compression attributes, data types, and so on. For complete details, see the ALTER TABLE statement.

Before you begin

To alter a table, you must have at least one of the following privileges on the table to be altered:

ALTER privilege
CONTROL privilege
DBADM authority
ALTERIN privilege on the schema of the table

You must have DBADM authority to:

Change the definition of an existing column.
Edit and test SQL when changing table columns.
Validate related objects when changing table columns.

Procedure

To change column properties:

Issue the ALTER TABLE statement.

For example, from the command line, enter:

   ALTER TABLE EMPLOYEE
      ALTER COLUMN WORKDEPT
         SET DEFAULT '123'