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How is a geometry stored in Oracle Spatial?
Oracle Spatial consists of a set of object data types, type methods, and operators, functions, and procedures that use these types. A geometry is stored as an object, in a single row, in a column of type SDO_GEOMETRY.
How are spatial aggregate functions defined in Oracle?
Many spatial aggregate functions accept an input parameter of type SDOAGGRTYPE. Oracle Spatial and Graph defines the object type SDOAGGRTYPE as: Do not use SDOAGGRTYPE as the data type for a column in a table. Use this type only in calls to spatial aggregate functions.
How is the SDO relate format used in Oracle?
SDO_RELATE Format. SDO_RELATE(geometry1, geometry2, params); Description. Uses the spatial index to identify either the spatial objects that have a particular spatial interaction with a given object such as an area of interest, or pairs of spatial objects that have a particular spatial interaction.
How is the SDO _ relate operator used in spatial?
The expression SDO_COVERS (geometry1,geometry2) = ‘TRUE’ evaluates to TRUE for object pairs that have the COVERS topological relationship, and FALSE otherwise. See the Usage Notes for the SDO_RELATE operator in this chapter. For an explanation of the topological relationships and the nine-intersection model used by Spatial, see Section 1.8.
Which is the SDO _ geometry object type in Oracle?
Oracle Spatial and Graph also defines the SDO_POINT_TYPE, SDO_ELEM_INFO_ARRAY, and SDO_ORDINATE_ARRAY types, which are used in the SDO_GEOMETRY type definition, as follows:
Where is the geometric description of an object stored?
With Spatial and Graph, the geometric description of a spatial object is stored in a single row, in a single column of object type SDO_GEOMETRY in a user-defined table. Any table that has a column of type SDO_GEOMETRY must have another column, or set of columns, that defines a unique primary key for that table.
How to get the dltt components of a geometry object?
The following methods are available for returning the individual DLTT components of the SDO_GTYPE for a geometry object: Get_Dims, Get_LRS_Dim, and Get_Gtype. These methods are described in SDO_GEOMETRY Methods.
When to delete a spatial index in Oracle?
If the index creation does not complete for any reason, the index is invalid and must be deleted with the DROP INDEX [FORCE] statement. Within each geometry column to be indexed, all the geometries must have the same SDO_SRID value. Spatial indexes can be built on two, three, or four dimensions of data.
How to query spatial data efficiently in Oracle?
Query spatial data efficiently, based on an understanding of the Oracle Spatial query model and primary and secondary filtering (see Section 5.2)
How is a spatial query used in multiprocessor system?
In a multiprocessor system environment, if a spatial operator is invoked on a table with partitioned spatial index and if multiple partitions are involved in the query, multiple processors can be used to evaluate the query.