Altering a table

Use the Alter Table notebook to alter a table.

Authorities and privileges

To alter a table:

1. Open the Alter Table notebook.

2. Perform one or more of these tasks depending on what you want to alter:
   • On the Table page, change table properties.

   • On the Columns page:
     • Click Add and add new columns using the Add Column notebook.

     • Select an existing column and click Change to use the Change Column notebook to modify its comment or, if it is a VARCHAR column, its length.

   • On the Primary Key page, define a new primary key or change the existing primary key. In both cases, the new primary key you define must be identical to one of the table's unique index keys. The keys are identical only if they have the same number of columns and the nth column name of one is the same as the nth column name of the other.
   • On the Foreign Key page:
     • Click Add and add new foreign keys using the Add Foreign Key window.

     • Select an existing foreign key and click Change to use the Change Foreign Key window to change the foreign key.

   • On the Check Constraints page:
     • Click Add and add new check constraints using the Add Check Constraint window.

     • Select an existing check constraint and click Change to use the Change Check Constraint window to change the check constraint.

3. Click OK to alter your table and close the Alter Table notebook.

Related information

• Creating a table
• Creating an index
• Checking data in table spaces