Obtaining a single unified result for a query over a plurality of data sources. A query specifies an identity of a type of data that the query is providing, and an identity of a format and type of data the query is looking for as a specific answer to the query. The query is mapped to a query pattern from among a plurality of available query patterns. A set of two or more different data sources are queried using one or more queries that correspond to the query pattern. At least two results of querying the particular set of two more different data sources are received. A single unified result is derived from at least one of the results. The single unified result has the format and type of data query specified that the query was looking for as a specific answer to the query.