Key Types
The Key Type identifies what sort of test the index supports. You can use one of three key types:
| Key Type | Description |
|---|---|
| Equality | The performances of tests that look for nodes with a specific value. |
| Presence | Improves the performance of tests that look for the existence of an node, regardless of its value. |
| Substring | Improves the performance of tests that look for a node whose value contains a given substring. This key type is best used when your queries use the XQuery contains() substring function. |