DATA DEFINITION LANGUAGE

Data Definition Language (DDL) is a set of SQL commands used to define and manipulate the structure of database objects such as tables, views, indexes, and sequences. It is a type of programming language that is used to create, modify, and delete database objects in a database management system (DBMS).

DDL statements are used to define the schema of a database, which includes the data types of each field in a table, primary and foreign key constraints, and any other constraints on the data. DDL commands include CREATE, ALTER, and DROP statements.

CREATE statements are used to create new database objects, ALTER statements are used to modify the structure of existing objects, and DROP statements are used to delete objects from the database.

Overall, DDL plays an important role in the management and maintenance of a database by allowing database administrators to define and modify the database schema, ensuring the accuracy and consistency of data stored in the database.





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