The quality of the data residing in information repositories and databases gets degraded due to a multitude of reasons. Such reasons include typing mistakes during insertion (e.g., character transpositions), lack of standards for recording database fields (e.g., addresses), and various errors introduced by poor database design (e.g., missing integrity constraints). Data of poor quality can result in significant impediments to popular business practices: sending products or bills to incorrect addresses, inability to locate customer records during service calls, inability to correlate customers across multiple services, etc.
