Space partitioned GiST (SP-GiST) has mainly been designed for in-memory use. The reason for this is an SP-GiST stored on disk needs a fairly high number of disk hits to function. Disk hits are way more expensive than just following a couple of pointers in RAM.
The beauty is that SP-GiST can be used to implement various types of trees such as quad- trees, k-d trees, and radix trees (tries).
The following strategies are provided:
|
Operation |
Strategy number |
|
Strictly left of |
1 |
|
Strictly right of |
5 |
|
Same |
6 |
|
Contained by |
8 |
|
Strictly below |
10 |
|
Strictly above |
11 |
To write your own operator classes for SP-GiST, a couple of functions have to be provided:
|
Function |
Description |
Support function ... |
