INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values (5706, 'EPSG', 5706, '+vunits=m +no_defs +type=crs', 'VERT_CS["Caspian depth",VERT_DATUM["Caspian Sea",2005,AUTHORITY["EPSG","5106"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Depth",DOWN],AUTHORITY["EPSG","5706"]]');