Nicely done! As we've already mentioned,
ST_Equals checks whether two geometries represent the same location or space.
ST_Equals ignores the order of vertices in a polygon, the starting point of a polygon, and even additional vertices that do not change its shape. Look at the image below:
ST_Equals will consider Figure 1, Figure 2, Figure 3, and Figure 4 to be equal, even though their representations are certainly different. Take a look at the following query:
FROM sf_hotels sh
JOIN sf_sights ss
As you can see, we passed in the
ST_Reverse function as one of the arguments to
ST_Reverse function returns a geometry with the vertex order reversed. So, if we had the linestring ABC, the
ST_Reverse function would return the linestring CBA.
In accordance with our earlier explanation, even though we reversed the vertex order of one of its arguments, the
ST_Equals function still returned
TRUE and gave us the same result.