Geometry Methods Supported by Spatial Indexes
Spatial indexes support the following set-oriented geometry methods under certain conditions: STContains(), STDistance(), STEquals(), STIntersects(), STOverlaps(), STTouches(), and STWithin(). To be supported by a spatial index, these methods must be used within the WHERE or JOIN ON clause of a query, and they must occur within a predicate of the following general form:
To return a non-null result, geometry1 and geometry2 must have the same spatial reference identifier (SRID). Otherwise, the method returns NULL.
Spatial indexes support the following predicate forms: