GreaterThanEqualExpression gte1 = new GreaterThanEqualExpression(plan, constant3, constant4);
EqualExpression eq1 = new EqualExpression(plan, constant0, constant1);
NotEqualExpression neq1 = new NotEqualExpression(plan, constant0, constant2);
CompilationMessageCollector collector = new CompilationMessageCollector();
TypeCheckingExpVisitor expTypeChecker = new TypeCheckingExpVisitor(
plan, collector, null);
expTypeChecker.visit();
plan.explain(System.out, "text", true);
printMessageCollector(collector);
// printTypeGraph(plan) ;