I think this is fine as long as it's a bottle problem -- something for the interview that is not of benefit to the business. If a company is asking you to do un

I think this is fine as long as it's a bottle problem -- something for the interview that is not of benefit to the business. If a company is asking you to do unpaid work on their existing database without paying you, it's unethical. I think in general asking you to do a coding assignment in the office is better than asking you to do homework because there is a cost (in terms of time invested) to the company. For homework, a company can ask dozens of applicants to invest hours of their time at minimum cost to the company, even when some of bthose applicants had no chance to begin with. Here, they're forced to be choosier.