1. A computer implemented method to track a plurality of queries and a plurality of result sets of entities, the method comprising: storing in a memory of a computer, as a first tuple, a first query of said plurality of queries and a first result set of said plurality of result sets, wherein the first result set is determined based on an execution of the first query over a symbol table of program source code and the first result set comprises one or more entries including one or more identifiers used in the program source code, and the first tuple is associating the first query with the corresponding first result set; storing in the memory, as a second tuple, a second query of the plurality of queries and a second result set of the plurality of result sets, wherein the second result set is determined based on an execution of the second query over the symbol table of the program source code and the second result set comprises metadata associated with the one or more identifiers retrieved by the first query and the second tuple is associating the second query with the corresponding second result set; retaining the first tuple and the second tuple in a data structure according to an order of execution of the first query and the second query; and navigating between the ordered first and second tuple to access multiple times at least one of the first and the second tuple.