a collection of meta-data that describes the relations in a database

a description of a particular collection of data, using a given data model

a description of the data in a database

a finite set of relation symbols with associated arities

a set of objects, a set of tables, and a function that assigns a natural number to each table (its arity, i

a set of relation schemes

The overall structure of the tables used to store information in the database.

The names of tables, fields, data types, and primary and foreign keys of a database. Also known as the database structure.

a description of a database. In this document, it refers to a description of the database's tables and their fields.

logically connected, usually owner-based, set of DBMS objects (tables, views, procedures etc).

The overall structure of the database tables that store information: user profile data, content metadata, or pure structured information. In the simplest case, a database schema has a single database table of user information. Each record (row) within this table might represent a unique customer, with each field (column) representing relevant customer information (address, city, phone number, etc.). More complex schema would involve multiple database tables related to one another through a common unique identifier. Such relational database tables are necessary for more complex data schemas for performance and easier administration.