INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values (7976, 'EPSG', 7976, '+vunits=m +no_defs +type=crs', 'VERT_CS["HKPD depth",VERT_DATUM["Hong Kong Principal Datum",2005,AUTHORITY["EPSG","5135"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Depth",DOWN],AUTHORITY["EPSG","7976"]]');