10. One or more non-transitory storage media storing instructions which, when executed by one or more computing devices, cause: for a query comprising a query block specifying a first join between a first table and a second table, making a first determination that the query block contains no post-join references to the second table to be processed after the first join, wherein the query block does not reference the second table in a SELECT, GROUP-BY, HAVING, or ORDER BY clause or subquery connecting or correlating conditions of the query block; wherein the first join is one of an outer join and a cross join; making a second determination that the query block is duplicate-insignificant; and in response to making the first determination and the second determination, transforming the query into a transformed query, wherein the second table is eliminated from a corresponding query block in the transformed query.
10. One or more non-transitory storage media storing instructions which, when executed by one or more computing devices, cause: for a query comprising a query block specifying a first join between a first table and a second table, making a first determination that the query block contains no post-join references to the second table to be processed after the first join, wherein the query block does not reference the second table in a SELECT, GROUP-BY, HAVING, or ORDER BY clause or subquery connecting or correlating conditions of the query block; wherein the first join is one of an outer join and a cross join; making a second determination that the query block is duplicate-insignificant; and in response to making the first determination and the second determination, transforming the query into a transformed query, wherein the second table is eliminated from a corresponding query block in the transformed query. 13. The one or more non-transitory storage media of claim 10 , wherein at least one of the first table and the second table is a base table or a view table.