2.2 PostgreSQL Concept

PostgreSQL is a relational database management system (RDBMS). This means that it is a system for managing data that is stored in relational form. A relationship is actually a mathematical salutation to a table . Today, the concept of storing data in the table is fast becoming a common sense, but there are other ways to organize the database. Files and directories on Unix-like operating systems form an example of a hierarchical database. The more modern development is the object-oriented database.

Each table is a collection of named rows . Each row consists of a set of identical named Fields . And each field has a specific type. Although the position of each field in each row is fixed, it is important to remember that SQL does not guarantee the order of the rows in the table (but you can explicitly sort them out).

Tables comprise a database, a collection of databases managed by a PostgreSQL server that forms a DB cluster .

2.2 PostgreSQL Concept