13. A computer program product, the computer program product tangibly embodied on a non-transitory computer-readable storage medium and including instructions that, when executed by at least one processor, are configured to: generate a new operator to add to a structured query language (SQL) query optimization process of a query by a query optimizer under a generic operator framework, wherein, under the generic operator framework, the new operator has a generic operator data structure that includes specifications for input attributes, output attributes and bypass attributes of the new operator; hold the generic operator data structure of the new operator in a knowledge base container; build, on query compile, the generic operator data structure of the new operator with reference only to the specifications for input attributes, output attributes and bypass attributes of the new operator; and apply optimization rules based on the generic operator data structure of the new operator during the structured query language (SQL) query optimization process of the query by the query optimizer.
13. A computer program product, the computer program product tangibly embodied on a non-transitory computer-readable storage medium and including instructions that, when executed by at least one processor, are configured to: generate a new operator to add to a structured query language (SQL) query optimization process of a query by a query optimizer under a generic operator framework, wherein, under the generic operator framework, the new operator has a generic operator data structure that includes specifications for input attributes, output attributes and bypass attributes of the new operator; hold the generic operator data structure of the new operator in a knowledge base container; build, on query compile, the generic operator data structure of the new operator with reference only to the specifications for input attributes, output attributes and bypass attributes of the new operator; and apply optimization rules based on the generic operator data structure of the new operator during the structured query language (SQL) query optimization process of the query by the query optimizer. 17. The computer program product of claim 13 , the instructions further configured to: receive a request for generating the new operator; and extend the query optimizer using the knowledge based container by determining whether the query optimizer is able to support the new operator.