A MySQL Tutorial Basic Database Terminology

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A MySQL Tutorial Basic Database Terminology.pdf ebook Many relational database concepts are really quite simple. In fact, much of the appeal of relational databases stems from the simplicity of their foundational concepts. Structural Terminology Within the database world, MySQL is classified as a relational database management system (RDBMS). That phrase breaks down as follows: • The database (the "DB" in RDBMS) is the repository for the information you want to store, structured in a simple, regular fashion: o The collection of data in a database is organized into tables. o Each table is organized into rows and columns. o Each row in a table is a record. o Records can contain several pieces of information; each column in a table corresponds to one of those pieces. • The management system (the "MS") is the software that lets you use your data by allowing you to insert, retrieve, modify, or delete records. • The word "relational" (the "R") indicates a particular kind of DBMS, one that is very good at relating (that is, matching up) information stored in one table to information stored in another by looking for elements common to each of them. The power of a relational DBMS lies in its capability to pull data from those tables conveniently and to join information from related tables to produce answers to questions that can't be answered from individual tables alone. Here's an example that shows how a relational database organizes data into tables and relates the information from one table to another. Suppose that you run a Web site that includes a banner-advertisement service. You contract with companies that want their ads displayed when people visit the pages on your site. Each time a visitor hits one of your pages, you serve an ad embedded in the page that is sent to the visitor's browser and assess the company a small fee. To represent this information, you maintain three tables. One table, company, has columns for company name, number, address, and telephone number. Another table, ad, lists ad numbers, the number for the company that "owns" the ad, and the amount you charge per hit. The third table, hit, logs each ad hit by ad number and the date on which the ad was served. (see example below)

A MySQL Tutorial Basic Database Terminology

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