1. A computer-implemented method comprising: (a) generating, using a data federation computer system, electronic configuration triple data structures for each of a plurality of data sources by performing the following steps for each of the plurality of data sources: i. identifying, using a data federation computer system, the respective data source; ii. identifying, using the data federation computer system, respective access data used to access the respective data source; iii. converting, by the data federation computer system, the respective access data to corresponding electronic configuration triple data structures based at least in part upon a common configuration ontology; and iv. storing in non-transitory computer-readable memory comprising at least one triplestore database, by the data federation computer system, the electronic configuration triple data structures; (b) generating, using the data federation computer system, a generated metadata ontology for each of the plurality of data sources by performing the following steps for each of the plurality of data sources: i. accessing, by the data federation computer system, the respective data source using the respective access data identified by the respective electronic configuration triple data structures; ii. extracting, by the data federation computer system, respective metadata from the respective data source, wherein the respective metadata identifies respective data specified in respective data structures; iii. converting, by the data federation computer system, the extracted respective metadata to corresponding respective electronic metadata triple data structures based at least in part upon a common metadata ontology; and iv. storing in the non-transitory computer-readable memory, by the data federation computer system, the respective electronic metadata triple data structures to form a respective generated metadata ontology for each respective data source; (c) generating, using the data federation computer system, a domain ontology corresponding to a first target data environment, wherein the first target data environment comprises a respective lexicon for specifying queries of the plurality of data sources; (d) storing, using the data federation computer system, the domain ontology; (e) for each of the plurality of data sources, generating, using the data federation computer system, a bridge ontology comprising an electronic mapping between the generated metadata ontology for the respective data source and the domain ontology; (f) determining, by the data federation computer system, a subset of the plurality of data sources that cannot be queried in place; (g) generating, by the data federation computer system, a re-hosted data ontology for each of the subset of the plurality of data sources by performing the following steps for each of the subset of the plurality of data sources: i. extracting, by the data federation computer system, respective data from the respective data source; ii. converting, by the data federation computer system, the respective extracted data to corresponding electronic data triple data structures based upon the respective bridge ontology; and iii. storing in the non-transitory computer-readable memory, by the data federation computer system, the electronic data triple data structures to form a re-hosted data ontology; and (h) correlating, by the data federation computer system, a query expressed in the domain ontology to the data from the plurality of data sources using the re-hosted data ontologies for each of the subset of the plurality of data sources and using the bridge ontologies for the remaining data sources.