After you create a table and save the table in an IBM® database, you can use the IBM Table Designer to make changes to some of the features in the table definition.
The features that you can change depend on the operating system of
the DB2® server.
The following table lists the possible changes to table features, and notes for each of the operating systems and data server products whether a change is supported in the IBM Table Designer:
| Feature Description | DB2 for Linux®, UNIX®, and Windows® | DB2 for z/OS® V8, V9, and V10 | DB2 for i V5R4 and V6R1 | IDS V11.10, V11.50, and V11.70 |
|---|---|---|---|---|
| Change table name | Yes | Yes | Yes | Yes |
| Change table comment | Yes | Yes | Yes | N/A |
| Add column | Yes | Yes | Yes | Yes |
| Delete column | No | No | No | No |
| Change column properties: | ||||
| Name | No | No | No | No |
| Data type | No | Yes1 | No | No |
| Length, scale, precision | No | Yes2 | No | No |
| Allow nulls | No | No | No | No |
| Default value | No | No | No | No |
| Formula | No | No | No | N/A |
| Identity | Yes | Yes | Yes | Yes |
| Comment | Yes | Yes | Yes | N/A |
| Add primary key | Yes | Yes | Yes | Yes |
| Delete primary key | Yes | Yes | Yes | Yes |
| Yes | ||||
| Add unique keys | Yes | Yes | Yes | Yes |
| Delete unique keys | Yes | Yes | Yes | Yes |
| Add foreign keys | Yes | Yes | Yes | Yes |
| Delete foreign keys | Yes | Yes | Yes | Yes |
| Add check constraints | Yes | Yes | Yes | Yes |
| Delete check constraints | Yes | Yes | Yes | Yes |
1 New data type must be compatible with existing data type. Existing data type cannot be an identity column, or type ROWID, LOB, DATE, TIME, TIMESTAMP, or distinct types. The TIMESTAMP data type cannot be changed to TIMESTAMP WITH TIMEZONE [available in Version 10 new function mode (NFM) only], or vice versa.
2 Column length, scale, and precision properties can be changed for compatible data types
See Also
Developing IBM Database Tables | Changing Table Definitions | IBM Table Designer
.NET Development Forum DB2 FAQs IDS FAQs
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