Appendix B. SQL Language Tutorial

SQL Language Tutorial

What Is SQL?

When you go to Google and request information, that request is called a query, and the search engine will collect any Web pages that match your query. To narrow the search, you might have to refine your request with more descriptive keywords. The same process applies to database lookups. When you make requests to a database, the request follows a certain format, and the database server will try to locate the information and return a result. The way in which you query the database is defined by the query language you are using. The standard language for communicating with relational databases is SQL, ...

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