1. A computer-implemented method for generating statistics for processing database queries, the method comprising: receiving a plurality of database queries by a database system, the database queries processing data stored in database tables of the database system; identifying missing statistics while generating execution plans for database queries, the identifying comprising, for each of the plurality of database queries: requesting a statistical information useful for generating an execution plan for a database query; determining that the requested statistical information is not available; and storing information describing the requested statistical information as missing statistics, responsive to determining that the requested statistical information is not available; and performing statistical analysis to determine at least a subset of the identified missing statistics for use in generating execution plans for subsequent database queries.