Description

st_may_contain is the index-friendly cheap upper-bound counterpart of st_contains. It returns 1 if outer might contain inner based on bounding-box and chain-box tests, and 0 when it definitely cannot. False positives are possible, false negatives are not, so the function is suitable as a pre-filter before the expensive exact st_contains check. The optional precision argument controls how tight the bounding test is.

st_get_chainbox returns the array of bounding boxes that make up the geometry's spatial-index chain-box decomposition, or SQL NULL when the geometry has no chain-box cache. Each element of the returned vector is itself a BOX geometry inheriting the SRID and float/double flag of the input. Mainly useful for debugging spatial-index behaviour and for diagnostic visualisations.

st_dv_geo_length returns the on-disk length in bytes of the serialized geometry contained in the raw row-encoding buf, counting both the header and the payload. This is a storage-engine helper used while walking row-formatted data and is not normally invoked from application code.

See Also

st_contains, st_within, st_intersects, st_may_intersect, st_get_bounding_box