从 RD 转换为 WGS84 时，Oracle SDO_CS.TRANSFORM 会移动坐标

Question

I have a Oracle database with spatial data in which coordinates are stored in RD format (srid 28992). To place them on a map (leaflet with openstreetmap) I need the coordinates in WGS84 (srid 4326) format.

I should be able to get the coordinates in that format by using SDO_CS.TRANSFORM. When I do that, all coordinates seems to be shifted eastwards by about 6m.

The verify that there was no problem with the data stored in the table, I created a query that takes RD coordinate 155000, 463000 and converts it to WGS84. From that query I get: 52,1551639130507 5,38735225721137

If I do the same transformation on op http://www.gpscoordinaten.nl/converteer-gps-coordinaten.php I get 52.15517, 5.38721 (which is the right coordinate)

The query used is this one:

SELECT
  t.X,
  t.Y
FROM
  (
    SELECT
      SDO_CS.TRANSFORM( MDSYS.SDO_GEOMETRY( 2001, 28992, MDSYS.SDO_POINT_TYPE(
      155000, 463000, NULL ), NULL, NULL ), 4326 ) AS geometry
    FROM
      dual
  )
  geo,
  TABLE( SDO_UTIL.GETVERTICES( geo.geometry ) ) t;

Any idea why the conversion in Oracle is shifting the coordinates?

Answer 1

Have a look at this http://epsg.io/28992

PROJCS["Amersfoort / RD New",
    GEOGCS["Amersfoort",
        DATUM["Amersfoort",
            SPHEROID["Bessel 1841",6377397.155,299.1528128,
                AUTHORITY["EPSG","7004"]],
            TOWGS84[565.417,50.3319,465.552,-0.398957,0.343988,-1.8774,4.0725],
            AUTHORITY["EPSG","6289"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4289"]],
    PROJECTION["Oblique_Stereographic"],
    PARAMETER["latitude_of_origin",52.15616055555555],
    PARAMETER["central_meridian",5.38763888888889],
    PARAMETER["scale_factor",0.9999079],
    PARAMETER["false_easting",155000],
    PARAMETER["false_northing",463000],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AXIS["X",EAST],
    AXIS["Y",NORTH],
    AUTHORITY["EPSG","28992"]]

But for Oracle select wktext3d from cs_srs where srid = 28992; you get

PROJCS[ "Amersfoort / RD New", 
    GEOGCS["Amersfoort", 
        DATUM["Amersfoort", 
        SPHEROID[ "Bessel 1841", 6377397.155, 299.1528128, 
            AUTHORITY["EPSG", "7004"]], 
        TOWGS84[593.16, 26.15, 478.54, -1.304398008226, -0.103297414969, -1.144501530423, 4.0775], 
            AUTHORITY["EPSG", "6289"]], 
        PRIMEM["Greenwich", 0.000000, 
            AUTHORITY["EPSG","8901"]], 
        UNIT["degree (supplier to define representation)", 0.0174532925199433, 
            AUTHORITY["EPSG", "9122"]], 
        AXIS["Lat", NORTH], 
        AXIS["Long", EAST], 
        AUTHORITY["EPSG", "4289"]], 
    PROJECTION ["Oblique Stereographic"], 
    PARAMETER ["Latitude_Of_Origin", 52.1561605555555556], 
    PARAMETER ["Central_Meridian", 5.3876388888888889], 
    PARAMETER ["Scale_Factor", 0.9999079], 
    PARAMETER ["False_Easting", 155000.0], 
    PARAMETER ["False_Northing", 463000.0], 
    UNIT["metre", 1.0, 
        AUTHORITY["EPSG", "9001"]], 
    AXIS["X", EAST], 
    AXIS["Y", NORTH], 
    AUTHORITY["EPSG", "28992"]]

You see the TOWGS84 parameters are different.

Maybe you should discuss the issue at https://gis.stackexchange.com/ or ask Oracle support if they put wrong data in their reference.

Add-on

Check official EPSG data at http://www.epsg-registry.org/

When you search for

• Tpye = CoordinateTransformation - Single
• Arae = Netherland

You get a bunch of transformations. I think you have to make some deeper investigations.

Answer 2

For those landing here with a similar problem.

As pointed out in the accepted answer there are various values out there for the transformation parameters. To change the transformation parameters in Oracle for SRID 28992 you have to do the following:

update mdsys.sdo_datums set
  shift_x = 565.2369,
  shift_y = 50.0087,
  shift_z = 465.658,
  rotate_x = -0.406857330322398,
  rotate_y = 0.350732676542563,
  rotate_z =  -1.8703473836068 ,
  scale_adjust = 4.0812
where datum_id = 6289;

commit;

begin SDO_CS.UPDATE_WKTS_FOR_EPSG_DATUM(6289);
end;

commit;

I took me some time to figure out that Oracle caches these values. In order for these changes to take effect, you have to log out and start a new session.