Data Manipulation Language (DML) Language for accessing and updating the data organized by the appropriate data model DML also known as query language There are basically two types of data-manipulation language Procedural DML--require a user to specify what data are needed and how to get those data. 。 Declarative DML --require a user to specify what data are needed without specifying how to get those data. Declarative DMLs are usually easier to learn and use than are procedural DMLs. Declarative DMLs are also referred to as non-procedural DMLs The portion of a dML that involves information retrieval is called a query language. Database System Concepts-7th Edition 1.18 ©Silberscha乜，Korth and SudarshanDatabase System Concepts - 7 1.18 ©Silberschatz, Korth and Sudarshan th Edition Data Manipulation Language (DML) ▪ Language for accessing and updating the data organized by the appropriate data model • DML also known as query language ▪ There are basically two types of data-manipulation language • Procedural DML -- require a user to specify what data are needed and how to get those data. • Declarative DML -- require a user to specify what data are needed without specifying how to get those data. ▪ Declarative DMLs are usually easier to learn and use than are procedural DMLs. ▪ Declarative DMLs are also referred to as non-procedural DMLs ▪ The portion of a DML that involves information retrieval is called a query language