Oracle 9i Index-Organized Tables IOT

An Index-Organized Table (IOT) is a unique storage organization feature of the Oracle9i server that provides added value in performance, scalability, and availability over conventional tables.  The actual data for an index-organized table is stored in B-tree index leaves in sorted order based on the table's primary key so that changes to that data, such as adding, updating, or deleting rows, require an update t o the index only.  This approach enables extremely fast access to table data for primary key based queries, making index-organized tables ideal for a wide variety of applications.