The data source code identifying the data source from which the record was loaded.

the type of data construct this row represents

The optional match key describing why the record merged into the entity to which it belongs. This may be absent or null if this record belongs to a single-record entity or if it was the inital record of the first multi-record entity to which it belonged (even if it later re-resolved into a larger entity).

The optioanl principle identifying the resolution rule that was used to merge the record into the entity to which it belonss. This may be absent or null if this record belongs to a single-record entity or if it was the inital record of the first multi-record entity to which it belonged (even if it later re-resolved into a larger entity).

The record ID that uniquely identifies the record within the data source from which it was loaded.