DataBase System Data Definition Language Data Definition Language Ddl) provide the abilities to setting up a database Cg Ddl allows the specification of not only a set of relations but also information about each relation Including s The schema for each relation t The domain of values associated with each attribute u Integrity constraints a The set of indices to be maintained for each relations H Security and authorization information for each relation H The physical storage structure of each relation on disk Haichang Gao, Software School, Xidian UniversityDataBase System Haichang Gao , Software School , Xidian University 7 Data Definition Language Data Definition Language (DDL) provide the abilities to setting up a database. DDL allows the specification of not only a set of relations but also information about each relation, including:  The schema for each relation.  The domain of values associated with each attribute.  Integrity constraints  The set of indices to be maintained for each relations.  Security and authorization information for each relation.  The physical storage structure of each relation on disk