DATAOBJ_TO_MAT_PARTITION is useful only to Data Cartridge developers who are performing data maintenance or query operations on system-partitioned tables that are used to store domain index data. The DML or query operations are triggered by corresponding operations on the base table of the domain index.
This function takes as arguments the name of the base table and the partition ID of the base table partition, both of which are passed to the function by the appropriate ODCIIndex method. The function returns the materialized partition number of the corresponding system-partitioned table, which can be used to perform the operation (DML or query) on that partition of the system-partitioned table.
If the base table is interval partitioned, then Oracle recommends that you use this function instead of the
DATAOBJ_TO_PARTITION function. The
DATAOBJ_TO_PARTITION function determines the absolute partition number, given the physical partition identifier. However, if the base table is interval partitioned, then there might be holes in the partition numbers corresponding to unmaterialized partitions. Because the system partitioned table only has materialized partitions,
DATAOBJ_TO_PARTITION numbers can cause a mis-match between the partitions of the base table and the partitions of the underlying system partitioned index storage tables. The
DATAOBJ_TO_MAT_PARTITION function returns the materialized partition number (as opposed to the absolute partition number) and helps keep the two tables in sync. Indextypes planning to support local domain indexes on interval partitioned tables should migrate to the use of this function.