Also called "tables," table datasets ara a dataset type that you can create and curate over time with the Table Editor, if you have the Splunk Datasets Add-on installed. You can derive the initial data for a table dataset from a combination or indexes and source types, an existing dataset, or a search string.
Table datasets have all of the features of other dataset types. You additionally can clone them as well as extend them. You can also accelerate table datasets, using the same process as data model acceleration.
In the Knowledge Manager Manual: