EPSG:6927 — SVY21 / Singapore TM + SHD height

COMPOUNDCRS[
    "SVY21 / Singapore TM + SHD height",
    PROJCRS[
        "SVY21 / Singapore TM",
        BASEGEOGCRS[
            "SVY21",
            DATUM[
                "SVY21",
                ELLIPSOID[
                    "WGS 84",
                    6378137,
                    298.257223563,
                    LENGTHUNIT["metre",1,ID["EPSG",9001]],
                    ID["EPSG",7030]
                ],
                ID["EPSG",6757]
            ],
            ID["EPSG",4757]
        ],
        CONVERSION[
            "Singapore Transverse Mercator",
            METHOD["Transverse Mercator",ID["EPSG",9807]],
            PARAMETER[
                "Latitude of natural origin",
                1.36666666666694,
                ANGLEUNIT["degree",0.0174532925199433,ID["EPSG",9102]],
                ID["EPSG",8801]
            ],
            PARAMETER[
                "Longitude of natural origin",
                103.833333333334,
                ANGLEUNIT["degree",0.0174532925199433,ID["EPSG",9102]],
                ID["EPSG",8802]
            ],
            PARAMETER[
                "Scale factor at natural origin",
                1,
                SCALEUNIT["unity",1,ID["EPSG",9201]],
                ID["EPSG",8805]
            ],
            PARAMETER[
                "False easting",
                28001.642,
                LENGTHUNIT["metre",1,ID["EPSG",9001]],
                ID["EPSG",8806]
            ],
            PARAMETER[
                "False northing",
                38744.572,
                LENGTHUNIT["metre",1,ID["EPSG",9001]],
                ID["EPSG",8807]
            ],
            ID["EPSG",19864]
        ],
        CS[Cartesian,2,ID["EPSG",4500]],
        AXIS["Northing (N)",north],
        AXIS["Easting (E)",east],
        LENGTHUNIT["metre",1,ID["EPSG",9001]],
        ID["EPSG",3414]
    ],
    VERTCRS[
        "SHD height",
        VDATUM["Singapore Height Datum",ID["EPSG",1140]],
        CS[vertical,1,ID["EPSG",6499]],
        AXIS["Gravity-related height (H)",up],
        LENGTHUNIT["metre",1,ID["EPSG",9001]],
        ID["EPSG",6916]
    ],
    ID["EPSG",6927]
]

+proj=tmerc +lat_0=1.36666666666667 +lon_0=103.833333333333 +k=1 +x_0=28001.642 +y_0=38744.572 +ellps=WGS84 +units=m +vunits=m +no_defs +type=crs

proj4.defs("EPSG:6927", "+proj=tmerc +lat_0=1.36666666666667 +lon_0=103.833333333333 +k=1 +x_0=28001.642 +y_0=38744.572 +ellps=WGS84 +units=m +vunits=m +no_defs +type=crs");

{
  "type": "CoordinateReferenceSystem",
  "code": 6927,
  "name": "SVY21 / Singapore TM + SHD height",
  "kind": "compound",
  "area": "Singapore",
  "unit": null,
  "bbox": [
    1.13,
    103.59,
    1.47,
    104.07
  ],
  "proj4": "+proj=tmerc +lat_0=1.36666666666667 +lon_0=103.833333333333 +k=1 +x_0=28001.642 +y_0=38744.572 +ellps=WGS84 +units=m +vunits=m +no_defs +type=crs"
}

INSERT INTO spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext)
VALUES (6927, 'EPSG', 6927, '+proj=tmerc +lat_0=1.36666666666667 +lon_0=103.833333333333 +k=1 +x_0=28001.642 +y_0=38744.572 +ellps=WGS84 +units=m +vunits=m +no_defs +type=crs', 'COMPD_CS["SVY21 / Singapore TM + SHD height",PROJCS["SVY21 / Singapore TM",GEOGCS["SVY21",DATUM["SVY21",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6757"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4757"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",1.36666666666667],PARAMETER["central_meridian",103.833333333333],PARAMETER["scale_factor",1],PARAMETER["false_easting",28001.642],PARAMETER["false_northing",38744.572],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AUTHORITY["EPSG","3414"]],VERT_CS["SHD height",VERT_DATUM["Singapore Height Datum",2005,AUTHORITY["EPSG","1140"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Gravity-related height",UP],AUTHORITY["EPSG","6916"]],AUTHORITY["EPSG","6927"]]');

PROJECTION
  "+proj=tmerc"
  "+lat_0=1.36666666666667"
  "+lon_0=103.833333333333"
  "+k=1"
  "+x_0=28001.642"
  "+y_0=38744.572"
  "+ellps=WGS84"
  "+units=m"
  "+vunits=m"
  "+no_defs"
  "+type=crs"
END

6927=COMPD_CS["SVY21 / Singapore TM + SHD height",PROJCS["SVY21 / Singapore TM",GEOGCS["SVY21",DATUM["SVY21",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6757"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4757"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",1.36666666666667],PARAMETER["central_meridian",103.833333333333],PARAMETER["scale_factor",1],PARAMETER["false_easting",28001.642],PARAMETER["false_northing",38744.572],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AUTHORITY["EPSG","3414"]],VERT_CS["SHD height",VERT_DATUM["Singapore Height Datum",2005,AUTHORITY["EPSG","1140"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Gravity-related height",UP],AUTHORITY["EPSG","6916"]],AUTHORITY["EPSG","6927"]]