Find overlapping slivers inside a postgis geometry table

find_overlapping_slivers.sql

-- Given that "mytable" have at least two field "id" and "geom" (Polygon/Multipolygon)

WITH
temp AS (
        SELECT distinct (st_dump(st_intersection(a.geom, b.geom))).geom AS geom --Use of distinct to remove symetrical shapes and st_dump().geom to get standard types
           FROM mytable a JOIN mytable b 
           ON a.id <> b.id AND st_intersects(a.geom, b.geom) --Filter to only test distinct object that intersects
          WHERE st_geometrytype(st_intersection(a.geom, b.geom)) = 'ST_GeometryCollection'::text --Filter to only include collections because areas are returned as collections
        )

SELECT row_number() OVER () AS id, temp.geom
   FROM temp
WHERE st_geometrytype(temp.geom) = 'ST_Polygon'::text --Filter to keep only polygon as line and point are normal topological intersection objects