7. A system, comprising: a processor; a data bus coupled to the processor; and a non-transitory, computer-readable storage medium embodying computer program code, the non-transitory, computer-readable storage medium being coupled to the data bus, the computer program code interacting with a plurality of computer operations and comprising instructions executable by the processor to cause the system to perform operations comprising: perform a region division structured query language (SQL) statement rewrite operation on the SQL statement, the region division SQL statement rewrite operation identifying a plurality of SQL statement regions; specify a rewrite focus priority for a particular SQL statement region in the plurality of SQL statement regions, the rewrite focus priority providing an indication of the particular amount of resource to be expended on a particular SQL statement region during an optimization operation on the particular SQL statement region, the rewrite focus priority indicating that the optimization operation is to be performed on the particular SQL statement region before other SQLs statement region in the plurality of SQL statement regions; perform a region preferential SQL statement optimization operation on the particular SQL statement region based on the rewrite focus priority indicating that the optimization operation is to be performed on the particular SQL statement region before other SQLs statement region in the plurality of SQL statement regions and based upon the indication of the particular amount of resource to be expended on the particular SQL statement region, the SQL statement optimization operation recursively performing a rewrite optimization on the particular SQL statement region according to the specified rewrite focus priority.
7. A system, comprising: a processor; a data bus coupled to the processor; and a non-transitory, computer-readable storage medium embodying computer program code, the non-transitory, computer-readable storage medium being coupled to the data bus, the computer program code interacting with a plurality of computer operations and comprising instructions executable by the processor to cause the system to perform operations comprising: perform a region division structured query language (SQL) statement rewrite operation on the SQL statement, the region division SQL statement rewrite operation identifying a plurality of SQL statement regions; specify a rewrite focus priority for a particular SQL statement region in the plurality of SQL statement regions, the rewrite focus priority providing an indication of the particular amount of resource to be expended on a particular SQL statement region during an optimization operation on the particular SQL statement region, the rewrite focus priority indicating that the optimization operation is to be performed on the particular SQL statement region before other SQLs statement region in the plurality of SQL statement regions; perform a region preferential SQL statement optimization operation on the particular SQL statement region based on the rewrite focus priority indicating that the optimization operation is to be performed on the particular SQL statement region before other SQLs statement region in the plurality of SQL statement regions and based upon the indication of the particular amount of resource to be expended on the particular SQL statement region, the SQL statement optimization operation recursively performing a rewrite optimization on the particular SQL statement region according to the specified rewrite focus priority. 12. The system of claim 7 , wherein: the specifying is provided via a user-specified input where the user is able to inference how to rewrite the SQL statement.