ADD COLUMN

To add columns to an existing table, use the ADD COLUMN setting with the ALTER TABLE command.

In this command, the syntax for adding columns is as follows:

ADD [COLUMN] column_name data_type [ NODEFAULT | NOMODIFY | HIDDEN ]

When you add columns, you must specify the column name and data type. You can also specify optional properties.

You cannot add primary keys to an existing table.

When a new column is added to the table using the NODEFAULT clause, any INSERT statements that are sent from the probes or gateways fail. The failure occurs because they do not comply with the NODEFAULT constraint.

When you mark a column as NODEFAULT and a row is inserted into that table, the insert statement must explicitly set a value for that column or the INSERT statement becomes invalid.

This occurs because the INSERT statement will not attempt to populate the NODEFAULT column. The trigger will also be invalid and cannot be successfully recompiled.