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Data model Schema and Instance The data which is stored in the database at a particular moment is called an instance of the database. The overall design of a database is called schema A database schema is the skeleton structure of the database. It represents the logical view of the entire database. A schema includes schema objects such as tables, foreign keys, primary keys, views, columns, data types, stored procedures, etc. A database schema can be represented using a visual diagram. This diagram shows the database objects and their relationship with each other. A database schema is designed by database designers so that the programmers whose software will interact with the database. The process of database creation is called data modeling. A schema diagram can display some aspects of a type of schema named record types, data types and constraints. Other aspects cannot be specified through a schema diagram. The given figures, for example, show neither the data type of each data item n...