Defining an Operator Class for Other Secondary-Access Methods

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Defining an Operator Class for Other Secondary-Access Methods

You can also define operator classes for user-defined secondary-access methods. A user-defined secondary-access method is one that a database developer has defined to implement a particular type of index. These access methods might have been defined in the database by a DataBlade module.

Tip:

You can examine the sysams system catalog table to determine which secondary-access methods your database defines. For information on the columns of the sysams system catalog table, see the IBM Informix: Guide to SQL Reference.

When you define an operator class on a user-defined secondary-access method, you provide support and strategy functions just as you do when you create an operator class on the generic B-tree index. You must be careful to conform to any operator class requirements of the user-defined secondary-access class. Before you implement an operator class for a user-defined secondary-access method, consult the documentation for the method.

You perform the same steps to define an operator class on a user-defined secondary-access method as you use to define an operator class on the generic B-tree index. (See Creating a New B-Tree Operator Class .) The only difference is that to create the index, you must specify the name of the user-defined secondary-access method in the USING clause of the CREATE INDEX statement.