assertion searching through datasource

Would it be possible to have a feature so that it searches through the datasource to find a match

for instance, let say i am placing a 'content assertion' on an element 'A'. I have a datasource grid or datasource jdbc with records 'A', 'B', 'C'. in the expected results of the assertion, it would be helpful, if I can specify 'search datasource jdbc/grid' for the element 'A'


Thanks

Ali