Quality of Data is one of the most important assets, and there are different methods for data quality assurance, there are also different tools to help keeping quality of data high. Microsoft Fortunately has a tool released as part of SQL Server 2012 named DQS (Data Quality Services) for this purpose. DQS works on a knowledge base driven data quality method. This means For keeping high quality of the data you have to build a good knowledge base contains domains, composite domains, and domain rules. The person or people involved in building and enhancement of that knowledge based called as Data Stewart. DQS also has some components for data matching as well.

There are five main types of data quality issues that DQS can resolve, which illustrated below as; Completeness, Accuracy, Conformity, Consistency, and Uniqueness.