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The relational model is a widely used database framework based on predicate logic. It was developed by Dr. Edgar F. Codd in 1969 and uses SQL to query data. The model is flexible, easily updated, and can be accessed by many applications.
The relational model is a simple, yet concise, framework for database storage, retrieval, and management, and as of 2011, it is the framework most used by databases over the last 40 years. The first actual use of the database model was in 1969, when its founder, Dr. Edgar F. Codd, wrote a report for his employer, IBM, and used the basic structure of the relational model to develop your relationship. The report was greeted with amazement. Dr. Codd was quickly enabled to delve into not only the basic structure, but also the operations of what would become the Relational Model for databases. A query language, a structured query language (SQL) was built around the relational model for use in querying data in relational databases built on top of the framework.
All programmers and program developers are educated in the concepts and operations of the relational model and can program around its structure. Since a relational model uses predicate logic in a declarative method and is based on mathematical terms of a two-way logic of true and false, any data related by this logic is subsequently operated on by relational calculus and relational algebra. These mathematical operations make the data not only easily queryable, but also easily updated with just a few steps in adding a row to a table. By using variables to quantify information with data values, the relational model also uses specific keys to enforce constraints on the use and querying of information. From the very beginning, Dr. Codd has used attributes to specify data types, and consistency has been built into the relational model, which has propelled it to become the ultimate database management tool.
In operation, the information in a relational model database is decomposed into smaller components that can be restructured in many ways to form larger pictures, depending on the variables queried in relation to the data and by linking many of the smaller components in relation to each other. the other. These small components are called entities and organized into a table of columns and rows. Information can be entered using any format and is stored according to a set of logical rules that follow specified design principles. Unique keys identify entities and preserve referential integrity and hence, a query will always find the same result since there is no duplication of information. Because this structure makes the relational database so flexible, programmers can write for the database to be accessible to many divergent applications.
Many commercial and open source products have been built around the relational model since the late 1960s, and most use the SQL query language to match components of predicate logic in a relational database. While you don’t need to use all the features of SQL, which supports three-valued logic, it can still easily query a relational database. There are at least 30 languages other than SQL, however, that are capable of handling databases and querying a relational database. SQL was simply the first language used with the initial relational model database developed.
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