Doc'd database functions for overlaps lookup.
@@ -372,6 +372,17 @@ Oracle ``SDO_GEOM.VALIDATE_GEOMETRY_WITH_CONTEXT(poly, 0.05
*Availability*: `PostGIS <https://postgis.net/docs/ST_Overlaps.html>`__,
Oracle, MySQL, SpatiaLite, PGRaster (Bilateral)
+Tests if the geometry field spatially overlaps the lookup geometry.
+
+========== ============================
+Backend SQL Equivalent
+========== ============================
+PostGIS ``ST_Overlaps(poly, geom)``
+Oracle ``SDO_OVERLAPS(poly, geom)``
+MySQL ``MBROverlaps(poly, geom)``
+SpatiaLite ``Overlaps(poly, geom)``
+========== ============================
+
.. fieldlookup:: relate
``relate``
