Oracle SDO_TOPO_GEOMETRY Datatype

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Example of SDO_TOPO_GEOMETRY Datatype in Oracle 21c

This article will explore the SDO_TOPO_GEOMETRY data type in Oracle 21c, including its syntax, advantages, and example usage.

Introduction to Oracle SDO_TOPO_GEOMETRY Datatype

Oracle 21c introduced the spatial data type SDO TOPO GEOMETRY, which is intended to facilitate topology in spatial data. SDO TOPO GEOMETRY offers a way to store and manage the relationships between the spatial objects in a dataset, which is referred to as topology.

Being a composite data type, SDO TOPO GEOMETRY consists of various different data types. It has two components in particular: a geometry component and a topology component. While the topology component represents the connections between the objects, geometry represents the object’s actual location and shape.

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Advantages of SDO_TOPO_GEOMETRY Datatype

  • Better query performance is one of the main benefits of utilizing SDO TOPO GEOMETRY because it enables faster spatial queries. Queries can be performed much more quickly by precalculating the topology relationships between items than if the relationships had to be traversed at query time.
  • More flexibility is possible when establishing topology rules and relationships between items thanks to SDO TOPO GEOMETRY. This enables the development of more intricate and accurate spatial datasets.
  • SDO TOPO GEOMETRY offers a more organized way to manage spatial data, which results in better data management. Topology relationships can be stored in a distinct component, making it simpler to update and manage the data over time.
  • Integration of other Oracle features is simple: SDO TOPO GEOMETRY is made to function with other Oracle features like the Spatial and Graph data without any issues.
  • Support for a wide range of spatial data types: SDO_TOPO_GEOMETRY supports a wide range of spatial data types, including points, lines, polygons, and more. This makes it possible to use the data type for a variety of different spatial applications and use cases.

Syntax of SDO_TOPO_GEOMETRY Datatype in Oracle 21c

The syntax for creating a column with the SDO_TOPO_GEOMETRY datatype in Oracle 21c is as follows:

SDO_TOPO_GEOMETRY(
    geometry SDO_GEOMETRY,
    topology SDO_TOPOLOGY
)

The geometry parameter specifies the geometry component of the object, which represents the spatial location and shape of the object. It is a mandatory parameter and must be specified.

The topology parameter specifies the topology component of the object, which represents the relationships between objects in the dataset. It is an optional parameter and can be specified as NULL if no topology is required.

The SDO_GEOMETRY and SDO_TOPOLOGY data types are both predefined data types in Oracle 21c. The SDO_GEOMETRY type is used to define the spatial location and shape of an object, while the SDO_TOPOLOGY type is used to define the topology relationships between objects.

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Example of SDO_TOPO_GEOMETRY Datatype in Oracle 21c

Here is an example of SDO_TOPO_GEOMETRY Datatype in Oracle 21c.

CREATE TABLE traffic_signs ( sign_id NUMBER, sign_type VARCHAR2(20), location SDO_TOPO_GEOMETRY );

In this example, we created the table ‘traffic_signs’ and then assign the column name ‘sign_id’, ‘sign_type’, and location.

Next, we will insert the values into the following given table.

INSERT INTO traffic_signs VALUES (
  SDO_TOPO_GEOMETRY(
    1,
    3000,
    'CITY_DATA',
    SDO_ELEM_INFO_ARRAY(1,1,1),
    SDO_ORDINATE_ARRAY(5)
  )
);
Example of SDO_TOPO_GEOMETRY Datatype in Oracle 21c
Example of SDO_TOPO_GEOMETRY Datatype in Oracle 21c

Disadvantages of SDO_TOPO_GEOMETRY Datatype in Oracle 21c

  • Complexity: Compared to other geometry data types, the SDO TOPO GEOMETRY data type is more complicated and requires extensive knowledge to use effectively.
  • Storage needs: Because SDO TOPO GEOMETRY objects contain more topology-related data than other geometry kinds, they require more storage space.
  • Performance: If the topology is complex, topological queries may run more slowly than non-topological searches. Performance may suffer and query times may lengthen as a result.
  • Restricted support: SDO TOPO GEOMETRY is not supported by all spatial tools and applications, which may limit its applicability in some circumstances.
  • Migration challenges: Switching to SDO TOPO GEOMETRY from other geometry types can be challenging because it necessitates major modifications to programs and data structures.

Features of SDO_TOPO_GEOMETRY Datatype in Oracle 21c

  • Topological relationships: The storage and manipulation of topological relationships between geometric objects is made possible by SDO TOPO GEOMETRY. Complex geographical analysis techniques, like network analysis and topology-aware queries, are now possible.
  • Points, lines, polygons, and multi-part objects are just a few of the geometric types supported by SDO TOPO GEOMETRY.
  • Complicated structures can be created with SDO TOPO GEOMETRY, including topologically enabled networks and graphs.
  • Checking for consistency: SDO TOPO GEOMETRY automatically verifies the consistency of topological relationships to maintain the accuracy and dependability of the data.
  • Spatial indexing is supported by SDO TOPO GEOMETRY and can significantly boost the speed of spatial queries and analyses.
  • Interoperability of data It is simple to exchange data with other systems because to SDO TOPO GEOMETRY’s support for common spatial data exchange formats as the Open Geospatial Consortium (OGC) standard.

Conclusion

In this article, we have discussed the SDO_TOPO_GEOMETRY data type in Oracle 21c, including its syntax, advantages, and example usage.

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