A system includes reception of a first query to search two or more heterogeneous data providers, generation of a first query language excerpt to define a combined key column based on key columns associated with a first data provider of the two or more heterogeneous data providers, for each of two or more columns of the first data provider, generation of a second query language excerpt to map the column of the first data provider to a respective result set key column and a respective result set value column, generation of a third query language excerpt to identify two or more of the result set value columns to search, and generation of a first query language statement based on the first, second and third query language excerpts.