DB2® UDB for iSeries™ makes indexes a powerful tool.
The following table summarizes some of the differences between binary radix indexes and encoded vector indexes:
| Binary Radix Indexes | Encoded Vector Indexes | |
|---|---|---|
| Basic data structure | A wide, flat tree | A Symbol Table and a vector |
| Interface for creating | Command, SQL, iSeries Navigator | SQL, iSeries 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, via dynamic bitmaps or RRN list |
| Used for joining | Yes | Yes (in conjunction with a hash table) |
| Used for grouping | Yes | Yes |
| Used for ordering | Yes | No |
| Used to enforce unique Referential Integrity constraints | Yes | No |
