DataViewRow.GetIdGetter Method
Definition
Important
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A getter for a 128-bit ID value. It is common for objects to serve multiple DataViewRow instances to iterate over what is supposed to be the same data, for example, in a IDataView a cursor set will produce the same data as a serial cursor, just partitioned, and a shuffled cursor will produce the same data as a serial cursor or any other shuffled cursor, only shuffled. The ID exists for applications that need to reconcile which entry is actually which. Ideally this ID should be unique, but for practical reasons, it suffices if collisions are simply extremely improbable.
Note that this ID, while it must be consistent for multiple streams according to the semantics above, is not considered part of the data per se. So, to take the example of a data view specifically, a single data view must render consistent IDs across all cursorings, but there is no suggestion at all that if the "same" data were presented in a different data view (as by, say, being transformed, cached, saved, or whatever), that the IDs between the two different data views would have any discernible relationship.
public abstract Microsoft.ML.ValueGetter<Microsoft.ML.Data.DataViewRowId> GetIdGetter ();abstract member GetIdGetter : unit -> Microsoft.ML.ValueGetter<Microsoft.ML.Data.DataViewRowId>Public MustOverride Function GetIdGetter () As ValueGetter(Of DataViewRowId)