TRANSFORMING A SINGLE-TABLE JOIN PREDICATE INTO A PSEUDO-JOIN PREDICATE

Methods, computing devices, and computer-readable media are provided for transforming an initial query with a single-table outer join predicate to a second, semantically equivalent query that includes a multi-table predicate instead of the single-table outer join predicate. Because the second query does not include the single-table outer join predicate, the second query may be available for further transformations or optimization techniques, may produce a more efficient or otherwise different execution plan, or may be executed more efficiently or differently. The single-table outer join predicate may be in a full outer join ON clause of the initial query or nested in a left outer-joined LATERAL VIEW of the initial query. The multi-table predicate may be in a WHERE clause of the second query. Unlike the initial query, the second query allows use of a temporary organization of data from multiple tables for evaluation of multiple rows of the left outer join.