SDO_CS.DETERMINE

Format

SDO_CS.DETERMINE_CHAIN(
     transient_rule_set IN SDO_TRANSIENT_RULE_SET, 
     use_case           IN VARCHAR2, 
     source_srid        IN NUMBER, 
     target_srid        IN NUMBER) RETURN TFM_PLAN;

Description

Returns the query chain, based on the system rule set, to be used in transformations from one coordinate reference system to another coordinate reference system.

Parameters

transient_rule_set: Rule set to be used for the transformation. If you specify a null value, the Oracle system rule set is used.
use_case: Use case for which to determine the query chain. Must be a null value or a value from the USE_CASE column of the SDO_PREFERRED_OPS_USER table (described in SDO_PREFERRED_OPS_USER Table).
source_srid: The SRID of the source coordinate reference system. Must be a value in the SRID column of the SDO_COORD_REF_SYS table (described in SDO_COORD_REF_SYS Table).
target_srid: The SRID of the target coordinate reference system. Must be a value in the SRID column of the SDO_COORD_REF_SYS table (described in SDO_COORD_REF_SYS Table).

Usage Notes

This function returns an object of type TFM_PLAN, which is explained in TFM_PLAN Object Type.

The transient_rule_set parameter is of type SDO_TRANSIENT_RULE_SET, which has the following definition:

CREATE TYPE sdo_transient_rule_set AS OBJECT (
  source_srid  NUMBER,
  target_srid  NUMBER,
  tfm          NUMBER);

Examples

The following example returns the query chain based on the system rule set.

SELECT MDSYS.SDO_CS.DETERMINE_CHAIN(NULL, NULL, 4804, 4257) FROM DUAL;
 
MDSYS.SDO_CS.DETERMINE_CHAIN(NULL,NULL,4804,4257)(THE_PLAN)                     
--------------------------------------------------------------------------------
TFM_PLAN(SDO_TFM_CHAIN(4804, -2, 4257))

The next example creates a preferred concatenated operation (with operation ID 300) with a specified chain for transformations from SRID 4804 to SRID 4257, and then calls the DETERMINE_CHAIN function, returning a different result. (The operation created in this example is not meaningful or useful, and it was created only for illustration.)

CALL SDO_CS.CREATE_PREF_CONCATENATED_OP(
    300,
    'CONCATENATED OPERATION',
    TFM_PLAN(
      SDO_TFM_CHAIN(
                    4804,
        1000000001, 4804,
        1000000002, 4804,
        1000000001, 4804,
        1000000001, 4804,
        1000000002, 4804,
        1000000002, 4804,
        1000000001, 4804,
        1000000001, 4804,
        1000000001, 4804,
        1000000002, 4804,
        1000000002, 4804,
        1000000002, 4257)),
    NULL);
 
SELECT MDSYS.SDO_CS.DETERMINE_CHAIN(NULL, NULL, 4804, 4257) FROM DUAL;
 
MDSYS.SDO_CS.DETERMINE_CHAIN(NULL,NULL,4804,4257)(THE_PLAN)                     
--------------------------------------------------------------------------------
TFM_PLAN(SDO_TFM_CHAIN(4804, 300, 4257))