EPSG:19871

PROJECTION["Hotine_Oblique_Mercator"],
PARAMETER["latitude_of_center",4],
PARAMETER["longitude_of_center",102.25],
PARAMETER["azimuth",323.0257905],
PARAMETER["rectified_grid_angle",323.130102361111],
PARAMETER["scale_factor",0.99984],
PARAMETER["false_easting",804670.24],
PARAMETER["false_northing",0]

CONVERSION["Rectified Skew Orthomorphic Malaya Grid (chain)",
    METHOD["Hotine Oblique Mercator (variant A)",
        ID["EPSG",9812]],
    PARAMETER["Latitude of projection centre",4,
        ANGLEUNIT["degree",0.0174532925199433],
        ID["EPSG",8811]],
    PARAMETER["Longitude of projection centre",102.25,
        ANGLEUNIT["degree",0.0174532925199433],
        ID["EPSG",8812]],
    PARAMETER["Azimuth of initial line",323.0257905,
        ANGLEUNIT["degree",0.0174532925199433],
        ID["EPSG",8813]],
    PARAMETER["Angle from Rectified to Skew Grid",323.130102361111,
        ANGLEUNIT["degree",0.0174532925199433],
        ID["EPSG",8814]],
    PARAMETER["Scale factor on initial line",0.99984,
        SCALEUNIT["unity",1],
        ID["EPSG",8815]],
    PARAMETER["False easting",40000,
        LENGTHUNIT["British chain (Sears 1922 truncated)",20.116756],
        ID["EPSG",8806]],
    PARAMETER["False northing",0,
        LENGTHUNIT["British chain (Sears 1922 truncated)",20.116756],
        ID["EPSG",8807]],
    ID["EPSG",19871]]

PROJECTION["Rectified_Skew_Orthomorphic_Natural_Origin"],
PARAMETER["False_Easting",804670.24],
PARAMETER["False_Northing",0.0],
PARAMETER["Scale_Factor",0.99984],
PARAMETER["Azimuth",-36.9742095],
PARAMETER["Longitude_Of_Center",102.25],
PARAMETER["Latitude_Of_Center",4.0],
PARAMETER["XY_Plane_Rotation",-36.8698976388889]

proj4.defs("EPSG:19871","+proj=omerc +no_uoff +lat_0=4 +lonc=102.25 +alpha=323.0257905 +gamma=323.130102361111 +k=0.99984 +x_0=804670.24 +y_0=0");

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "Conversion",
    "name": "Rectified Skew Orthomorphic Malaya Grid (chain)",
    "method": {
        "name": "Hotine Oblique Mercator (variant A)",
        "id": {
            "authority": "EPSG",
            "code": 9812
        }
    },
    "parameters": [
        {
            "name": "Latitude of projection centre",
            "value": 4,
            "unit": "degree",
            "id": {
                "authority": "EPSG",
                "code": 8811
            }
        },
        {
            "name": "Longitude of projection centre",
            "value": 102.25,
            "unit": "degree",
            "id": {
                "authority": "EPSG",
                "code": 8812
            }
        },
        {
            "name": "Azimuth of initial line",
            "value": 323.0257905,
            "unit": "degree",
            "id": {
                "authority": "EPSG",
                "code": 8813
            }
        },
        {
            "name": "Angle from Rectified to Skew Grid",
            "value": 323.130102361111,
            "unit": "degree",
            "id": {
                "authority": "EPSG",
                "code": 8814
            }
        },
        {
            "name": "Scale factor on initial line",
            "value": 0.99984,
            "unit": "unity",
            "id": {
                "authority": "EPSG",
                "code": 8815
            }
        },
        {
            "name": "False easting",
            "value": 40000,
            "unit": {
                "type": "LinearUnit",
                "name": "British chain (Sears 1922 truncated)",
                "conversion_factor": 20.116756
            },
            "id": {
                "authority": "EPSG",
                "code": 8806
            }
        },
        {
            "name": "False northing",
            "value": 0,
            "unit": {
                "type": "LinearUnit",
                "name": "British chain (Sears 1922 truncated)",
                "conversion_factor": 20.116756
            },
            "id": {
                "authority": "EPSG",
                "code": 8807
            }
        }
    ],
    "id": {
        "authority": "EPSG",
        "code": 19871
    }
}

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=omerc +no_uoff +lat_0=4 +lonc=102.25 +alpha=323.0257905 +gamma=323.130102361111 +k=0.99984 +x_0=804670.24 +y_0=0">
	<Layer srs="+proj=omerc +no_uoff +lat_0=4 +lonc=102.25 +alpha=323.0257905 +gamma=323.130102361111 +k=0.99984 +x_0=804670.24 +y_0=0">
	</Layer>
</Map>

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 19871, 'EPSG', 19871, '+proj=omerc +no_uoff +lat_0=4 +lonc=102.25 +alpha=323.0257905 +gamma=323.130102361111 +k=0.99984 +x_0=804670.24 +y_0=0', 'PROJECTION["Hotine_Oblique_Mercator"],PARAMETER["latitude_of_center",4],PARAMETER["longitude_of_center",102.25],PARAMETER["azimuth",323.0257905],PARAMETER["rectified_grid_angle",323.130102361111],PARAMETER["scale_factor",0.99984],PARAMETER["false_easting",804670.24],PARAMETER["false_northing",0]');