Modify table behavior in a table hierarchy

After you define a table hierarchy, you cannot modify the structure (columns) of the existing tables. However, you can modify the behavior of tables in the hierarchy. Table behavior that you can modify in a table hierarchy shows the table behavior that you can modify in a table hierarchy and the syntax that you use to make modifications.

Table 1. Table behavior that you can modify in a table hierarchy

Table behavior	Syntax	Considerations
Constraint definitions	ALTER TABLE	To add or drop a constraint, use the ADD CONSTRAINT or DROP CONSTRAINT clause. For more information, see Constraints on tables in a table hierarchy.
Indexes	CREATE INDEX, ALTER INDEX	For more information, see Add indexes to tables in a table hierarchy and the CREATE INDEX and ALTER INDEX statements in the HCL OneDB™ Guide to SQL: Syntax.
Triggers	CREATE/DROP TRIGGER	You cannot drop an inherited trigger. However, you can drop a trigger from a supertable or add a trigger to a subtable to override an inherited trigger. For information about how to modify triggers on supertables and subtables, see Triggers on tables in a table hierarchy. For information about how to create a trigger, see the HCL OneDB Guide to SQL: Tutorial.

All existing subtables automatically inherit new table behavior when you modify a supertable in the hierarchy.