schema
Conceptually, a schema is a set of interrelated database objects, such as tables, table columns, data types of the columns, indexes, foreign keys, and so on. These objects are connected through SQL syntax, because the columns make up the tables, the foreign keys refer to tables and columns, and so on. Ideally, they are also connected logically, working together as part of a unified application or flexible framework. For example, the information-schema and performance-schema databases use "schema" in their names to emphasize the close relationships between the tables and columns they contain.
In MySQL, physically, a schema is synonymous with a database. You can substitute the keyword SCHEMA instead of DATABASE in MariaDB SQL syntax, for example using CREATE SCHEMA instead of CREATE DATABASE.
Some other database products draw a distinction. For example, in the Oracle Database product, a schema represents only a part of a database: the tables and other objects owned by a single user.
See also database.
See also ib-file set.
See also INFORMATION-SCHEMA.
See also Performance Schema.