Comparing binary radix indexes and encoded vector indexes
DB2® for IBM® i makes indexes a powerful tool.
The following table summarizes some of the differences between binary radix indexes and encoded vector indexes:
| Comparison value | Binary Radix Indexes | Encoded Vector Indexes |
|---|---|---|
| Basic data structure | A wide, flat tree | A Symbol Table and a vector |
| Interface for creating | Command, SQL, System i® Navigator | SQL, System i Navigator |
| Can be created in parallel | Yes | Yes |
| Can be maintained in parallel | Yes | Yes |
| Used for statistics | Yes | Yes |
| Used for selection | Yes | Yes, with dynamic bitmaps or RRN list |
| Used for joining | Yes | Yes (with a hash table) |
| Used for grouping | Yes | Yes |
| Used for ordering | Yes | No |
| Used to enforce unique Referential Integrity constraints | Yes | No |
| Source for predetermined or ready-made numeric aggregate results | No | Yes, with INCLUDE keyword option on create |