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Current Oracle Spatial Blog Articles

    Tip: Drop that Spatial Index!
    Convert Single Geometry to Multi-part Geometry in Oracle Spatial
    Optimized Rectangle to 5 Point Polygon
    Centroid Package now supports Y ordinate seeding
    Convert GeoJSON document to Sdo_Geometry objects
    Implementation Of Travelling Salesman Problem
    Create Polygon From Bearings And Distances
    Function That Returns a Compass Point From a Whole Circle Bearing
    Playing around with Centroids by using different seed values
    GeoRaptor 4.x Update 2
    Simple Oracle C Sprintf or Java String.format
    Some Oriented Point Functions
    Extracting Inner Rings Changed Ordinate Ordering: A Trap For Players Who Don't Read Documentation!
    PLS-00306: wrong number or types of arguments in call to 'SDO_GEOMETRY'
    Converting Google Earth Formatted Longitude/Latitude points to decimal degrees
    Oracle Business Intelligence Warehousing and Analytics - Spatial Summit
    How far inside, is inside? Measuring actual distance.
    Noding and building a polygon from single, overlapping linestrings
    Analyzing Spatial Query Performance Improvements in Oracle Spatial and Graph 12c Through Cross-Vendor Comparison
    ST_VertexN / ST_PointN - Extracting a specific point from any geometry
    Convert Single Point stored in SDO_ORDINATES to SDO_POINT_TYPE
    Aggregate APPEND Islands and XOR polygons
    Circular Arcs in Geodetic Polygons
    Some SDO_GEOMETRY/DIMINFO handling functions
    Applying And Extending Oracle Spatial - Book Released
    Changing all DIMINFO sdo_tolerance values for all metadata records in one go.
    Building Polygons from Incomplete Linestrings using ST_PolygonBuilder
    Computing Cardinal Directions to nearby geometries
    Intersecting two aggregated polygon layers with SC4O
    Spatial and Oracle 12c
    Update Triggers and SDO_GEOMETRY Equality
    Duplicate Geometry data and Data Models
    CENTROID package update
    How to calculate cumulative length of a linestring
    Useful Package of Wrapper Functions for Sdo_Util.AffineTransforms
    Compute Location from known Lat/Long point using delta easting and northing in miles
    SDO_AGGR_SET_UNION
    Sorting SDO_GEOMETRY data using the ORDER BY clause of a SELECT statement
    Creating linestrings from points
    Rounding Coordinates or Ordinates in SDO_GEOMETRY
    Effects of Sdo_Geometry Ordinate Precision on Performance
    Effects of Sdo_Geometry Ordinate Precision on Storage
    The Spatial filtering of geometries: The effect of tolerances on relationships
    Application of Delaunay Triangulation and Inverse Distance Weighting (IDW) in Oracle for Soils Interpolation
    Selecting all SDO_GTYPE values for all tables/sdo_geometry columns in a schema
    CENTROID package - Tips for Use
    Announcing the Spatial Companion For Oracle (SC4O)
    Filtering Rings (Oracle Spatial)
    Splitting a polygon using one or more linestrings
    isValid, isSimple, Dimension and CoordDim methods for SDO_Geometry
    Line Merging or Collecting lines together: ST_LineMerger
    ST_DeleteVertex for Oracle SDO_Geometry based on Jaspa/JTS
    3D/4D and SRID aware Conversion functions for SDO_Geometry: WKT and EWKT
    Topological vs Non-Topological Simplification/Generalization of Aggregated Area Geometies in Oracle
    Filtering very short linestrings via bitmap function index
    CENTROID For Oracle
    Gridding a sdo_geometry line/polygon object (Oracle)
    Finding centre and radius of a circular geometry
    Constraining geometry type for sdo_geometry column in a table.
    CASE Statements and SDO_GEOMETRY
    The Power of Constraints and Indexes for Spatial Constraints: stopping duplicate points
    Replacement for SDO_GEOM.RELATE - ST_Relate based on JTS
    Changing Oracle Spatial Index Parameters on existing index
    Writing Excel Spreadsheets files from within the Oracle database using Java and PL/SQL
    Writing xSV (eg csv) files from within the Oracle database using Java and PL/SQL
    A simple spike finder for Spatial/Locator
    JTS Java class compilation for 11g and above
    Random Spatial Search Procedure
    Geometry Snapping using JTS in Oracle
    Exposing JTS's MinimumBoundingCircle functionality
    Exposing JTS's Densifier functionality
    Using JTS's Comparison Functions - HausdorffSimilarityMeasure & AreaSimilarityMeasure with SDO_GEOMETRY
    Free JTS-based Area/Length Functions
    Handy way of systematically fixing polygon geometries with 13349 and other errors
    Standalone CENTROID package now available for download
    Free Union, Intersection, Xor and Difference Functions for Oracle Locator - Part 4 Processing Geodetic data
    Configurable Buffer: JTS and Oracle
    Free Union, Intersection, Xor and Difference Functions for Oracle Locator - Part 3
    Free Union, Intersection, Xor and Difference Functions for Oracle Locator - Part 2
    Free Union, Intersection, Xor and Difference Functions for Oracle Locator - Part 1
    Building Lines into Polygons in Oracle Locator / Spatial
    Finding Intersection Points between Line and Polygon
    SDO2GeoJSON
    Free version of sdo_length
    Alternative to my SQL based GetNumRings function
    External Tables and SDO_Geometry data.
    layer_gtype keyword issue when indexing linear data on 11g
    String Tokenizer for Oracle
    Free Aggregate Method for Concatenating 2D Lines in Oracle Locator 10g
    Reducing 5 Vertex Polygon to Optimized Rectangle
    Square Buffer
    Converting decimal seconds to string
    SDO_GEOM.VALIDATE_GEOMETRY_WITH_CONTEXT - 13356 Issues
    Valid conversion unit values for Oracle sdo_geom.sdo_length()
    Removing Steps in Gridded Vector Data - SmoothGrid for Oracle
    Oracle Spatial DISJOINT search/filtering
    Creating SDO_Geometry from geometric data recorded in the columns of a table
    Concave Hull Geometries in Oracle 11gR2
    Projecting SDO_GEOM_METADATA DIMINFO XY ordinates
    Instantiating MDSYS.VERTEX_TYPE
    New PL/SQL Packages - Rotate oriented point
    GeoRaptor Development Team
    Fast Refreshing Materialized View Containing SDO_GEOMETRY and SDO_GEOM.SDO_AREA function
    Performance of PL/SQL Functions using SQL vs Pure Code
    Implementing the BEST VicGrid Projection in Oracle 10gR2
    Making Sdo Geometry Metadata Update Generic Code
    ORA-13011 errors when using SDO_GEOM.VALIDATE_LAYER_WITH_CONTEXT()
    Extract Polygons from Compound Polygon
    Detecting sdo_geometries with compound (3-point Arcs) segments
    GEOMETRY_COLUMNS for Oracle Spatial
    Convert GML to SDO_Geometry in Oracle 10gR2
    Spatial Sorting of Data via Morton Key
    Swapping Ordinates in an SDO_GEOMETRY object
    New To_3D Function
    Extend (Reduce/Contract/Skrink) Function for Oracle
    Loading and Processing GPX 1.1 files using Oracle XMLDB
    Loading Spatial Data from an external CSV file in Oracle
    Calling the Oracle Spatial shapefile loader from within the Oracle database itself
    Implementing SDO_VertexUpdate/ST_VertexUpdate for Oracle
    Implementing SDO_RemovePoint/ST_RemovePoint for Oracle
    Implementing SDO_AddPoint/ST_AddPoint for Oracle
    ESRI ArcSDE Exverted and Inverted Polygons and Oracle Spatial
    Funky Fix Ordinates By Formula
    Implementing a SetPoint/ST_SetPoint function in Oracle
    Implementing an ST_SnapToGrid (PostGIS) function for Oracle Spatial
    Generating random point data
    Implementing an Affine/ST_Affine function for Oracle Spatial
    Implementing a Scale/ST_Scale function for Oracle Spatial
    Implementing a Parallel/ST_Parallel function for linestring data for Oracle Spatial
    Implementing a Rotate/ST_Rotate function for Oracle Spatial
    Limiting table list returned when connecting to Oracle Database using ODBC
    ST_Azimuth for Oracle: AKA Cogo.Bearing
    Implementing a Translate/ST_Translate/Move function for Oracle Spatial
    Elem_Info_Array Processing: An alternative to SDO_UTIL.GetNumRings and querying SDO_ELEM_INFO itself
    Minumum Bounding Rectangle (MBR) Object Type for Oracle
    How to extract elements from the result of an sdo_intersection of two polygons.
    How to restart a database after failed parameter change
    Fixing failed spatial indexes after import using data pump
    generate_series: an Oracle implementation in light of SQL Design Patterns
    Multi-Centroid Shootout
    Oracle Spatial Centroid Shootout
    On the use of ROLLUP in Oracle SELECT statements
    Surrounding Parcels
    Spatial Pipelining
    Using Oracle's SDO_NN Operator - Some examples
    Converting distances and units of measure in Oracle Locator
    Split Sdo_Geometry Linestring at a known point
    Forcing an Sdo_Geometry object to contain only points, lines or areas
    Unpacking USER_SDO_GEOM_METADATA's DIMINFO structure using SQL
    Generating multi-points from single point records in Oracle Spatial
    Object Tables of Sdo_Geometry
    Oracle Locator vs Oracle Spatial: A Reflection on Oracle Licensing of the SDO_GEOM Package
    FAST REFRESHing of Oracle Materialized Views containing Sdo_Geometry columns
    Australian MGA/AMG Zone Calculation from geographic (longitude/latitude) data
    Loading Shapefiles (SHP) into Oracle Spatial
    Oracle Spatial Mapping and Map Rendering Performance Tips
    The significance of sdo_lb/sdo_ub in USER_SDO_GEOM_METDATA: Do I need it?
    Oracle Spatial Forum - Melbourne April 2007
    Layer_GTypes for spatial indexes
    Oracle's SQL/MM Compliant Types
    Tips and Tricks

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All Blog Articles, Data Models and Free Source Code by Simon Greener, The SpatialDB Advisor is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

GEOMETRY_COLUMNS for Oracle Spatial

Sunday November 01 2009 at 08:24

Recently, I had cause to look at the implementation of the OGC/SQLMM Geometry_Columns and Spatial_Ref_Sys metadata views in Oracle.

ISO/TC 211, 6.2 Architecture — SQL implementation using Geometry Types, 6.2.1 Overview says:

“This standard defines a schema for the management of feature table, Geometry, and Spatial Reference System information in an SQL-implementation with a Geometry Type extension.”

Visually, this is:

OGC Metadata Tables

The definition of the Geometry_Columns table is as follows:

CREATE TABLE GEOMETRY_COLUMNS (
  F_TABLE_CATALOG   CHARACTER VARYING NOT NULL,
  F_TABLE_SCHEMA    CHARACTER VARYING NOT NULL,
  F_TABLE_NAME      CHARACTER VARYING NOT NULL,
  F_GEOMETRY_COLUMN CHARACTER VARYING NOT NULL,
  G_TABLE_CATALOG   CHARACTER VARYING NOT NULL,
  G_TABLE_SCHEMA    CHARACTER VARYING NOT NULL,
  G_TABLE_NAME      CHARACTER VARYING NOT NULL,
  STORAGE_TYPE      INTEGER,
  GEOMETRY_TYPE     INTEGER,
  COORD_DIMENSION   INTEGER,
  MAX_PPR           INTEGER,
  SRID              INTEGER NOT NULL
  REFERENCES SPATIAL_REF_SYS,
  CONSTRAINT GC_PK PRIMARY KEY
   (F_TABLE_CATALOG, F_TABLE_SCHEMA, 
    F_TABLE_NAME, F_GEOMETRY_COLUMN)
)

Oracle implements this table via a table called MDSYS.OGC_GEOMETRY_COLUMNS as follows:

CREATE TABLE MDSYS.OGIS_GEOMETRY_COLUMNS (
  F_TABLE_SCHEMA    VARCHAR2(64), 
  F_TABLE_NAME      VARCHAR2(64), 
  F_GEOMETRY_COLUMN VARCHAR2(64), 
  G_TABLE_SCHEMA    VARCHAR2(64), 
  G_TABLE_NAME      VARCHAR2(64), 
  STORAGE_TYPE      NUMBER, 
  GEOMETRY_TYPE     NUMBER, 
  COORD_DIMENSION   NUMBER, 
  MAX_PPR           NUMBER, 
  SRID              NUMBER, 
  CONSTRAINT FK_SRID FOREIGN KEY (SRID) REFERENCES
    MDSYS.OGIS_SPATIAL_REFERENCE_SYSTEMS (SRID) 
)

A few things must be noted:

  • There is no global GEOMETRY_COLUMNS view only Oracle-specific USER_GEOMETRY_COLUMNS and ALL_GEOMETRY_COLUMNS public views based on MDSYS.OGC_GEOMETRY_COLUMNS table.
  • The MAX_PPR and G_TABLE_SCHEMA/G_TABLE_NAME columns are no longer of any use as Oracle’s implementation of the Normalised model has long been dropped.
  • Oracle does not have concept of a CATALOG so F_TABLE_CATALOG was never supported.
  • STORAGE_TYPE should always be NULL = geometry types implementation (OGC SFS SQL 1.2)
  • Geometry_Type column is declared as a Number/Integer
  • For the GEOMETRY_TYPE column, the “use of a non-leaf Geometry class name from the Geometry Object Model for a geometry column implies that domain of the column corresponds to instances of the class and all of its subclasses” OGC 06-104r3, 7.1.3.3 Field description, Page 29

On top of this, no Oracle functions know of, or use, MDSYS.OGC_GEOMETRY_COLUMNS or the related views. Rather, all Oracle Spatial’s functionality uses the Oracle-specific metadata tables, the most basic being:

CREATE TABLE mdsys.sdo_geom_metadata_table (
   owner 	varchar2(32),
   table_name	varchar2(32),
   column_name	varchar2(32),
   diminfo 	mdsys.sdo_dim_array,
   srid 	number );

This table is needed mainly for creation of indexes. It is populated by user or client software: there is nothing automatic such that if a table with an sdo_geometry column (or more) is created, records are created in XXX_SDO_GEOM_METADATA>

In addition, Oracle does not automatically synchronise GEOMETRY_COLUMNS as DML is executed against the XXXX_SDO_GEOM_METADATA views. With manual DML executed against actual OGC_GEOMETRY_COLUMNS table or views generating the following error:

Error starting at line 1 in command:
insert into user_geometry_columns ( 
F_TABLE_SCHEMA,F_TABLE_NAME,F_GEOMETRY_COLUMN,STORAGE_TYPE,GEOMETRY_TYPE,COORD_DIMENSION,SRID
)
values('CODESYS','MORTON_P','GEOM',NULL,1,2,4326)
Error report:
SQL Error: ORA-02291: integrity constraint (MDSYS.FK_SRID) violated - parent key not found
02291. 00000 - "integrity constraint (%s.%s) violated - parent key not found"
*Cause:    A foreign key value has no matching primary key value.
*Action:   Delete the foreign key or add a matching primary key.

(There is no SRID in Spatial_Ref_Sys, which, itself, generates an error if you try and insert a correct spatial reference into it.)

So, how can one create a populated GEOMETRY_COLUMNS table such that open source or standards based software will be able to correctly interrogate the table/view?

One approach is to build a public view called GEOMETRY_COLUMNS over the existing Oracle metadata that is maintained as part of the normal course of events as follows:

CREATE VIEW GEOMETRY_COLUMNS 
AS
SELECT asgm.owner        as F_TABLE_SCHEMA,
       asgm.table_name   as F_TABLE_NAME,
       asgm.column_name  as F_GEOMETRY_COLUMN,
       NULL              as STORAGE_TYPE,
       Codesys.Get_Geometry_Type(asgm.owner,
                         asgm.table_name,
                         asgm.column_name)
                         as GEOMETRY_TYPE,
       (SELECT count(*) 
          FROM TABLE(asgm.diminfo)
       )                 as COORD_DIMENSION,
       asgm.SRID         as SRID
  FROM ALL_SDO_GEOM_METADATA asgm;

CREATE PUBLIC SYNONYM geometry_columns 
FOR codesys.geometry_columns;

(For performance reasons, this view would be better implemented as an “on demand” refreshable materialized view.)

The function Get_Geometry_Type() returns the correct OGC Geometry_Type. This function is as follows:

create or replace
Function Get_Geometry_Type( p_owner    in varchar2,
                            p_object   in varchar2,
                            p_geometry in varchar2,
                            p_text     in integer := 1)
 return varchar2 deterministic
AUTHID CURRENT_USER                       
  /* See:
     7.1.3 Geometry columns information
     7.1.3.3 Field description
     Table 4: Geometry type codes
     OGC SFS SQL 1.2 Document 
  */
As
  v_geometryType       integer;
  v_GeometryTypeString varchar2(100);
  v_exists             integer;
  v_sql                varchar2(4000);
Begin
  IF ( ' || p_geometry || ' is null ) Then
    Return 0;
  End If;
  BEGIN
    SELECT 1
      INTO v_exists
      FROM all_tab_columns a
     WHERE a.owner       = UPPER(p_owner)
       AND a.table_name  = UPPER(p_object)
       AND a.column_name = UPPER(p_geometry)
       AND a.data_type = 'SDO_GEOMETRY';
      EXCEPTION
         WHEN NO_DATA_FOUND THEN
           -- raise_application_error(-20001,'No table or view (' || p_owner || '.' || p_object || ') exists with sdo_geometry object called ' || p_geometry,true);
           return 0;
  END;
  v_sql := '
SELECT SUBSTR(GeometryType,1,100),
       OGC_GeometryType 
  FROM (
  SELECT b.GeometryType,
         CASE b.GeometryType
              WHEN ''GEOMETRY'' THEN 0
              WHEN ''POINT'' THEN 1
              WHEN ''LINESTRING'' THEN 2
              WHEN ''POLYGON'' THEN 3
              WHEN ''MULTIPOINT'' THEN 4
              WHEN ''MULTILINESTRING'' THEN 5
              WHEN ''MULTIPOLYGON'' THEN 6
              WHEN ''GEOMCOLLECTION'' THEN 7
              WHEN ''CURVE'' THEN 13
              WHEN ''SURFACE'' THEN 14
              WHEN ''POLYHEDRALSURFACE'' THEN 15
              WHEN ''GEOMETRYZ'' THEN 1000
              WHEN ''POINTZ'' THEN 1001
              WHEN ''LINESTRINGZ'' THEN 1002
              WHEN ''POLYGONZ'' THEN 1003
              WHEN ''MULTIPOINTZ'' THEN 1004
              WHEN ''MULTILINESTRINGZ'' THEN 1005
              WHEN ''MULTIPOLYGONZ'' THEN 1006
              WHEN ''GEOMCOLLECTIONZ'' THEN 1007
              WHEN ''CURVEZ'' THEN 1013
              WHEN ''SURFACEZ'' THEN 1014
              WHEN ''POLYHEDRALSURFACEZ'' THEN 1015
              WHEN ''GEOMETRY'' THEN 2000
              WHEN ''POINTM'' THEN 2001
              WHEN ''LINESTRINGM'' THEN 2002
              WHEN ''POLYGONM'' THEN 2003
              WHEN ''MULTIPOINTM'' THEN 2004
              WHEN ''MULTILINESTRINGM'' THEN 2005
              WHEN ''MULTIPOLYGONM'' THEN 2006
              WHEN ''GEOMCOLLECTIONM'' THEN 2007
              WHEN ''CURVEM'' THEN 2013
              WHEN ''SURFACEM'' THEN 2014
              WHEN ''POLYHEDRALSURFACEM'' THEN 2015
              WHEN ''GEOMETRYZM'' THEN 3000
              WHEN ''POINTZM'' THEN 3001
              WHEN ''LINESTRINGZM'' THEN 3002
              WHEN ''POLYGONZM'' THEN 3003
              WHEN ''MULTIPOINTZM'' THEN 3004
              WHEN ''MULTILINESTRINGZM'' THEN 3005
              WHEN ''MULTIPOLYGONZM'' THEN 3006
              WHEN ''GEOMCOLLECTIONZM'' THEN 3007
              WHEN ''CURVEZM'' THEN 3013
              WHEN ''SURFACEZM'' THEN 3014
              WHEN ''POLYHEDRALSURFACEZM'' THEN 3015
              ELSE 0
          END as OGC_GeometryType
    FROM (SELECT DISTINCT
                 CASE MOD(a.' || p_geometry || '.sdo_gtype,10) 
                      WHEN 0 THEN NULL
                      WHEN 1 THEN ''POINT'' 
                      WHEN 5 THEN ''MULTIPOINT'' 
                      WHEN 2 THEN CASE WHEN codesys.isCompound(a.' || p_geometry || '.sdo_elem_info) = 1 THEN ''CURVE''             ELSE ''LINESTRING''      END 
                      WHEN 6 THEN CASE WHEN codesys.isCompound(a.' || p_geometry || '.sdo_elem_info) = 1 THEN ''MULTICURVE''        ELSE ''MULTILINESTRING'' END
                      WHEN 3 THEN CASE WHEN codesys.isCompound(a.' || p_geometry || '.sdo_elem_info) = 1 THEN ''SURFACE''           ELSE ''POLYGON''         END
                      WHEN 7 THEN CASE WHEN codesys.isCompound(a.' || p_geometry || '.sdo_elem_info) = 1 THEN ''POLYHEDRALSURFACE'' ELSE ''MULTIPOLYGON''    END
                      WHEN 4 THEN ''GEOMETRYCOLLECTION''
                      ELSE NULL
                  END || 
                  CASE WHEN a.' || p_geometry || '.get_dims() > 2 
                            AND 
                            ( a.' || p_geometry || '.get_dims() = MOD(trunc(a.' || p_geometry || '.sdo_gtype/100),10) )
                       THEN ''Z'' 
                       ELSE CASE WHEN MOD(trunc(a.' || p_geometry || '.sdo_gtype/100),10) > 0 
                                 THEN ''M'' ELSE NULL 
                              END 
                   END as GeometryType
             FROM ' || p_owner || '.' || p_object || ' a
         ) b
    ORDER BY 1 DESC
    )
    WHERE rownum < 2';
dbms_output.put_line(v_sql);
    EXECUTE IMMEDIATE v_sql INTO v_GeometryTypeString, v_geometryType;
    RETURN CASE WHEN p_text = 1 
                THEN CASE WHEN v_geometryType = 0 THEN 'GEOMETRY' ElSE v_GeometryTypeString END
                ELSE TO_CHAR(v_geometryType) 
            END;
    EXCEPTION
      WHEN NO_DATA_FOUND THEN
        RETURN CASE WHEN p_text = 1 
                    THEN CASE WHEN v_geometryType = 0 or v_geometryType is NULL THEN 'GEOMETRY' ELSE v_GeometryTypeString END
                    ELSE TO_CHAR(v_geometryType) 
                END;
END Get_Geometry_Type;

Note that this function implements the OGC requirement for the GEOMETRY_TYPE column’s value to be “[…] a non-leaf Geometry class name from the Geometry Object Model for a geometry column implies that domain of the column corresponds to instances of the class and all of its subclasses” OGC 06-104r3, 7.1.3.3 Field description, Page 29

In other words, if the geometry_type is MULTIPOLYGON it includes the sub-type POLYGON.

Selecting on this table shows that it works:

select * 
  from geometry_columns gc
 where gc.f_table_schema = 'CODESYS';

F_TABLE_SCHEMA F_TABLE_NAME F_GEOMETRY_COLUMN GEOMETRY_TYPE COORD_DIMENSION SRID
CODESYS GEODPOINT2D GEOM POINT 2 8311
CODESYS GEODPOINT3D GEOM POINT 3 8311
CODESYS GEODPOLY2D GEOM POLYGON 2 8265
CODESYS MORTON_P GEOM POINT 2 0
CODESYS PROJ41014POLY2D GEOM POLYGON 2 41014
CODESYS PROJ41914POLY2D GEOM POLYGON 2 41014
CODESYS PROJCOMPOUND2D GEOM GEOMETRY 2 0
CODESYS PROJLINE2D GEOM LINESTRING 2 0
CODESYS PROJLINE3D GEOM LINESTRING 3 0
CODESYS PROJMULTIPOINT2D GEOM MULTIPOINT 2 0
CODESYS PROJMULTIPOINT3D GEOM MULTIPOINT 3 0
CODESYS PROJPOINT2D GEOM POINT 2 0
CODESYS PROJPOINT3D GEOM POINT 3 0
CODESYS PROJPOLY2D GEOM SURFACE 2 0
CODESYS PROJPOLY3D GEOM SURFACE 3 0
CODESYS QUAD GEOMETRY GEOMETRY 2 0


Note that, geometry_type is presented as text when the standard says INTEGER, recompiling the view using:

       CAST(Codesys.Get_Geometry_Type(asgm.owner,
                         asgm.table_name,
                         asgm.column_name,
                         0) AS INTEGER) 
                         as GEOMETRY_TYPE,

Will present the data correctly as an INTEGER.

After having done this work on a view I now have something that is:

  • Sustainable in that it is “automatic”, a part of the normal metadata management within Oracle.
  • And presents the right information to open source and OGC compliant software.

I hope this is of use to someone.

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