protected override bool Loop(ExecutionContext context)
{
var variable = context.Request.Context.FindVariable(IndexName);
var upperBound = ((SqlConstantExpression) UpperBound).Value;
var lowerBound = ((SqlConstantExpression) LowerBound).Value;
if (Reverse)
return variable.Evaluate(context.Request) >= lowerBound;
return variable.Evaluate(context.Request) < upperBound;
}