How are spatial reference systems supported in Oracle?
This chapter describes in greater detail the Oracle Spatial coordinate system support, which was introduced in Section 1.5.4. You can store and manipulate SDO_GEOMETRY objects in a variety of coordinate systems. For reference information about coordinate system transformation functions and procedures in the MDSYS.SDO_CS package, see Chapter 21.
What are the properties of a spatial reference?
Each part of the spatial reference has a number of properties (especially the coordinate system) that defines what map projection options are used to define horizontal coordinates. A SpatialReference object can also be accessed from existing datasets using the Describe spatialReference property.
When do you use spatial reference in a geodataset?
If the output is a stand-alone geodataset (not inside a feature dataset), the spatial reference properties are the same as the input geodataset’s spatial reference properties. If the input is a layer in a display, that spatial reference of the layer’s data source is used.
What is the alias of the spatial reference?
The alias of the spatial reference. The extent of the xy domain. The factory code of the spatial reference. The false origin and units. Indicates whether or not m-value precision information has been defined. Indicates whether or not xy precision information has been defined.
How are spatial queries used in the geodetic coordinate system?
Effective with release 9.2, ellipsoidal surface computations consider the curvatures of the Earth in the specified geodetic coordinate system and return correct, accurate results. In other words, Spatial queries return the right answers all the time.
Which is the most accurate spatial reference system?
For example, the New Hampshire State Plane local projection provides adequate accuracy for most spatial applications that use data for that state. However, Cartesian computations on a plane projection will never give accurate results for a large area such as Canada or Scandinavia.
What was the coordinate system before oracle9 I?
Before Oracle9 i, Spatial computations were based solely on flat (Cartesian) coordinates, regardless of the coordinate system specified for the layer of geometries.
When to use a shaded area in SDO _ intersection?
In Figure 23-3, the shaded area represents the polygon returned when SDO_INTERSECTION is used with a square ( geom1) and another polygon ( geom2 ). An exception is raised if geom1 and geom2 are based on different coordinate systems.
Is the coordinate system the same as the spatial system?
It enables the interpretation of a set of coordinates as a representation of a position in a real world space. The term coordinate reference system has the same meaning as coordinate system for Spatial, and the terms are used interchangeably.