This book assumes that you have a basic understanding of relational databases and the Structured Query Language (SQL). It will be easier for you to learn some of the advanced features of NHibernate if you already have a sound knowledge of SQL. This appendix gives a brief overview of the fundamentals of SQL. We highly recommend that you find a book to learn more about it.
A table, with its rows and columns, is a familiar sight to anyone who has worked with an SQL database. Sometimes you’ll see tables referred to as relations, rows as tuples, and columns as attributes. This is the language of the relational data model, the mathematical model that SQL databases (imperfectly) implement.