The ST_CoversFilter method provides an efficient test to determine if one geometry might cover the other.
Returns 1 if the geometry-expression might cover geo2, otherwise 0.
This test is cheaper than ST_Covers, but may return 1 in some cases where
the geometry-expression does not actually cover geo2.
Therefore, this method can be useful as a primary filter when further processing will determine whether geometries
interact in the desired way.
The implementation of ST_CoversFilter relies upon meta-data associated with the stored geometries.
Because the available meta-data may change between server versions, depending upon how the data is loaded, or
where ST_CoversFilter is used within a query,
the expression geometry-expression.ST_CoversFilter(geo2)
can return different results when geometry-expression does not cover
Whenever geometry-expression covers geo2,
ST_CoversFilter will always return 1.