We have spent a considerable amount of effort designing our database in order to make sure the data can be stored in a consistent and accurate way. In this chapter, we are going to look at how to get information back out again. The data will be stored in many separate tables, and depending on the questions we are asking, we will need to combine data from those tables in a number of different ways. This chapter is just a brief introduction to the art of querying. For further information you might be interested in looking at my book Beginning SQL Queries: From Novice to Professional.1
Simple Queries on One Table
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