Database schema

The database schema of a database system is its structure described in a formal language supported by the database management system (DBMS). The term 'schema' refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases). The formal definition of a database schema is a set of formulas (sentences) called integrity constraints imposed on a database. These integrity constraints ensure compatibility between parts of the schema. All constraints are expressible in the same language. A database can be considered a structure in realization of the database language. The states of a created conceptual schema are transformed into an explicit mapping, the database schema. This describes how real-world entities are modeled in the database.The requirements listed below influence the detailed structure of schemas that are produced. Certain applications will not require that all of these conditions are met, but these four requirements are the most ideal.Suppose we want a mediated (database) schema to integrate two travel databases, Go-travel and Ok-travel.In the context of Oracle Databases, a schema object is a logical data storage structure.