This chapter focuses on two important database design issues related to the integrity of databases: semantic and physical data integrity. First and foremost, enforcing database integrity means getting the correct results. This is fundamental.
The quality of data that is received from different sources can vary immensely. Efforts are currently underway to develop tools for data cleaning that allow users to estimate the reliability of uncertain data using Bayesian statistical methods, which can be used both to develop probability models for uncertain data and to improve the quality of uncertain data.