Added by berkley over 20 years ago
added support for the returnfield parameter
-QuerySpecification now sets a flag (containsExtendedSQL) when there are returnfield items in the pathquery document.
the accessor method containsExtendedSQL() can be called by other classes to check for extended return parameters
-getReturnFields returns a Vector of the names of each specified return field.
-printExtendedSQL returns a string of the extra SQL statements required for the query.
-a calling class should first check containsExtendedSQL to make sure that there are extra fields being returned, then call printExtendedSQL to
insert the extra SQL into the query. (Note that this is how DBQuery implements this.)