Sybase IQ join indexes support one-to-many join relationships. A simple example of a one-to-many relationship is a sales representative to a customer. A sales representative can have more than one customer, but a customer has only one sales representative.
There can be multiple levels of such relationships. However, you always specify join relationships between two tables, or between a table and a lower level join. The table that represents the “many” side of the relationship is called the top table.