A Schema is used for to define the design of database structure behind data organization and it is a visual representation data in different tables relationships enable the Schema’s underlying mission business rules for which the database is created. That term is used in discussing both relational databases and object-oriented databases. The term sometimes seems to refer to a visualization of a structure and sometimes to a formal text-oriented description. Schema diagrams also have an important function which are used for force database developers to transpose ideas to paper. It is mainly used for provides an overview of the entire database, while facilitating future database administrator work. According to the Oracle Database a schema is collection of database objects in which schema and user names are the same but function different a user may be deleted or reassigned to another user while its collection of objects Schema within the database remains intact.