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What Is a Query, and When Should You Use One?
Microsoft Access offers several different types of queries. This chapter focuses on the most basic type of query, the Select query. A Select query is a stored question about the data stored in your database's tables. Select queries are the foundation of much of what you do in Access. They underlie most of your forms and reports, allowing you to view the data you want, when you want. You use a simple Select query to define the tables and fields whose data you want to view and also to specify the criteria to limit the data the query's output displays. A Select query is a query of a table or tables that just displays data; it doesn't modify data in any way. You use more advanced Select queries to summarize data, supply the results of calculations, or cross-tabulate your data. You can use Action queries to add, edit, or delete data from your tables, based on selected criteria, but this chapter covers Select queries. Chapter 11, "Advanced Query Techniques," covers other types of queries.
