Methods for transforming a query to remove redundant tables and eliminate superfluous join operations is provided. The methods provided transform queries to remove redundant tables and anti-joins, semi-joins, and outer-joins. Whether a table is redundant is determined based on a set of criteria which, if fulfilled, indicates that the removal of the table and the anti-join, semi-join, or outer-join operation does not impact query results. The removal of a redundant table from a query also results in the elimination of the anti-join, semi-join, or outer-join operation that references the removed table.