US Patent 9542446 Automatic generation of composite datasets based on hierarchical fields

Datasets are annotated with metadata including categories. Each category corresponds to one or more fields. A hierarchy mapping is generated to indicate a hierarchical relationship between different categories. A natural language query specifies a first granularity level indicating a particular category and one or more field values corresponding to the particular category. Based on the hierarchy mapping, one or more categories that are hierarchically related to the particular category are identified. Based on the metadata, two or more datasets that include at least one hierarchically related category is selected. Based on the first granularity level, one or more dataset filters are generated. The one or more dataset filters are translated to a second granularity level corresponding to the at least one hierarchically related category. The translated filters are applied to at least one of the selected datasets. The two or more datasets are joined to generate a composite dataset.