1. A computer system comprising a memory for improved processing of expression-based data validation configured to: generate at least one token-based menu for an expression-builder user interface for a computer system database, wherein said token-based menu comprises a drop-down list of at least one token; display said expression-builder user interface of said computer system database comprising said at least one token-based menu to create a validation wherein said validation comprises a Boolean validation expression wherein execution of a validation expression returns a result that indicates integrity of data in a record of said computer system database; provide said expression-builder user interface to validate a plurality of records in said computer system; provide a calculation field in said memory coupled to said expression-builder user interface wherein said calculation field is cached in said memory at run time, said memory is external to said computer system database, and further wherein said calculation field comprises a computed value computed from token-based expressions describing data in said computer system database and further where said calculation field is coupled to said expression-builder user interface; obtain said computed value from said calculation field; execute said validation expression comprising said computed value to produce a Boolean truth result of validation for each of said plurality of records, and wherein said validation expression is further configured to set a tooltip value for a validation result column associated with said plurality of records on said user interface, and wherein said tooltip value shows a message that is associated with said validation; wherein when said Boolean truth result of validation comprises a failure, obtain a level of execution for said validation wherein said level of execution comprises a plurality of levels; and, return said Boolean truth result of validation for each of said plurality of records.