sql - a beginner's guide, 2nd edition (2003)

[...]... database, and modify data that has been added to that database SQL is the most widely implemented language for relational databases SQL not only allows you to manage data within the database, but also manage the database itself By using SQL statements, you can access an SQL database directly by using an interactive client application or through an application programming language or scripting language Regardless... both SQL and the relational data model CRITICAL SKILL 1.1 Understand Relational Databases Structured Query Language (SQL) supports the creation and maintenance of the relational database and the management of data within that database However, before I go into a discussion about relational databases, I want to explain what I mean by the term database The term itself has been used to refer to anything... Programming languages such as C or COBOL or scripting languages such as VBScript or JavaScript must often access a data source in order to retrieve or modify data through the application Many of these data sources are managed by a relational database management system (RDBMS) that relies on the Structured Query Language (SQL) to create and alter database objects, add data to and retrieve data from the database,... standard, which was dubbed SQL: 1999” (also known as SQL3 ) The SQL: 1999 standard, like its predecessor SQL- 92, is based on the relational data model, which defines how data can be stored and manipulated within a relational database Relational database management systems (RDBMSs) such as Oracle or SQL Server use the SQL standard as a foundation for their products, providing database environments that... attributes As you can see in Figure 1-1 , each attribute has an associated domain A domain defines the type of data that can be stored in a particular attribute; however, a domain is not the same thing as a data type A data type, which is discussed in more detail in Module 3, is a specific kind of constraint associated with a column, whereas a domain, as it is used in the relational model, has a much broader... data and allows that data to be manipulated in a way that is predictable and resistant to error The relational model, which is rooted primarily in the mathematical principles of set theory and predicate logic, supports easy data retrieval, enforces data accuracy and consistency, and provides a database structure independent of the applications accessing the stored data At the core of the relational... a collection of names and addresses to a complex system of data retrieval and storage that relies on user interfaces and a network of client computers and servers There are as many definitions for the word database as there are books about them Despite the lack of an absolute meaning, most sources agree that a database, at the very least, is a collection of data organized in a structured format that... broader meaning and describes exactly what data can be included in an attribute associated with that domain For example, the Copyright attribute is associated with the Year domain The domain can be defined so that the attribute includes only data whose values and format are limited to years, as opposed to days or months The domain might also limit the data to a specific range of years A data type, on... Introduction to Relational Databases and SQL Figure 1-1 Relation made up of the Artist, CDName, and Copyright attributes Data is stored in a relation in tuples (rows) A tuple is a set of data whose values make up an instance of each attribute defined for that relation Each tuple represents a record of related data (In fact, the set of data is sometimes referred to as a record.) For example, in Figure 1-1 the second... to define each clause that makes up the SELECT statement and how those clauses are processed when querying a database Module 8: Modifying SQL Data In this module, you’ll learn how to modify data in an SQL database Specifically, you’ll learn how to insert data, update data, and delete data The module reviews each component of the SQL statements that allow you to perform these data modifications Module . web-based and client-server applications and the databases that supported those applications. In addition, he has designed and implemented various Access and SQL Server databases and has used SQL to. Default screen About the Author Robert Sheldon has worked as a consultant and technical writer for a number of years. As a consultant, he has managed the development and maintenance of web-based. databases, create and modify database objects, query and modify data, and troubleshoot system- and data-related problems. Robert has also written or cowritten eight books on various network and