1
Connolly TM, Beg CE. Database systems: a practical approach to design, implementation, and management. Sixth edition. Harlow, Essex, England: : Pearson 2015. https://ebookcentral.proquest.com/lib/uea/detail.action?docID=5136720
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Lans RF van der. Introduction to SQL: mastering the relational database language. 4th ed. Upper Saddle River, N.J.: : Addison-Wesley 2006. https://www.oreilly.com/library/view/introduction-to-sql/0321305965/?ar