1. A computer-implemented method of managing statistics collections stored on a computer readable storage medium and used to optimize execution of queries associated with a database, the computer-implemented method comprising: (a) determining whether one or more of the statistic collections are unnecessary for optimization of at least one query associated with the database, by determining whether a re-generated query execution plan, for the at least one query, that does not use the one or more of the statistics collections is equivalent to an original query execution plan for the at least one query, that uses the one or more statistics collections; and eliminating the one or more statistic collections from the computer readable storage medium when the determining (a) determines that the one or more statistic collections are unnecessary.