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The following types of indexes are supported:
A primary key index is an index for the primary key columns in a particular table.
You can have only one primary key index for each table, although each index can include multiple columns.
A primary key index is unique, so the indexed columns cannot have duplicate values nor can they be null (empty). For example, a customer phone number must be unique in order to locate a particular customer record.
A primary key index for each table that has one or more primary key columns is automatically created.
A foreign key index is an index for one or more foreign key columns in a particular table. A foreign key index is automatically created for each set of foreign key columns that migrate through a relationship.
A unique index that provides an alternative unique index in addition to the primary key index. For example, to locate a customer quickly, the primary key index may include only the customer account number. As an alternative, the alternate key index may include the customer phone number column, which must be a unique number associated with a customer record.
A non-unique, or inversion entry index lets you quickly access records using values that are not unique, such as EMPLOYEE last name. Duplicate values in the inversion entry index are allowed.
In a Logical/Physical model, if you create an index in the physical model, the corresponding key group in the logical model is automatically created. A key group is a logical modeling tool that identifies relationships between entities that are implemented as foreign keys. You can also use key groups to identify potential primary keys or alternate keys for use in the physical model.
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