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Structure of the relational database
The relational model is the basis for any relational database management system (RDBMS).A relational model has three ponents: a collection of objects or relations, operators that act on the objects or relations, and data integrity methods. In other words, it has a place to store the data, a way to create and retrieve the data, and a way to make sure that the data is logically consistent.
A relational database uses relations, or two-dimensional tables, to store the information needed to support a business. Let's go over the ponents of a traditional relational database system and look at how a relational database is designed. Once you have a solid understanding of what rows, columns, tables, and relationships are, you'll be well on your way to leveraging the power of a relational database.
Tables, Rows, and Columns
A table in a relational database, alternatively known as a relation, is a two-dimensional structure used to hold related information. A database consists of one or more related tables.
Note:Don't confuse a relation with relationships. A relation is essentially a table, and a relationship is a way to correlate, join, or associate two tables.
A row in a table is a collection or instance of one thing, such as one employee or one line Item on an invoice. A column contains all the information of a single type, and the piece o