Default Operator Classes

Each secondary-access method has a default operator class that is associated with it. By default, the CREATE INDEX statement associates the default operator class with an index. For example, the following CREATE INDEX statement creates a B-tree index on the zipcode column and automatically associates the default B-tree operator class with this column:

CREATE INDEX zip_ix ON customer(zipcode)

For each of the secondary-access methods that Dynamic Server provides, it provides a default operator class, as follows:

• The default B-tree operator class is a built-in operator class.

  The database server implements the operator-class functions for this operator class and registers it as btree_ops in the system catalog tables of a database.

• The default R-tree operator class is a registered operator class.

  The database server registers this operator class as rtree_ops in the system catalog tables. The database server does not implement the operator-class functions for the default R-tree operator class.

DataBlade modules can provide other types of secondary-access methods. If a DataBlade module provides a secondary-access method, it might also provide a default operator class. For more information, refer to your DataBlade module user's guide.

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