This is extremely true, but also make sure you know the law/length of time involved. If your not REQUIRED to give them info, you should not. Read and understand how it works first. However if at all you might even slightly be required to disclose it, then make sure you disclose it, because if you get hired, start training, then they find out, they will fire you, and you will now have to explain why you got paid by xxx airline for only 2 weeks.