Semi-Structured Data Many applications require storage of complex data,whose schema changes often The relational model's requirement of atomic data types may be an overkill E.g.,storing set of interests as a set-valued attribute of a user profile may be simpler than normalizing it Data exchange can benefit greatly from semi-structured data Exchange can be between applications,or between back-end and front-end of an application Web-services are widely used today,with complex data fetched to the front-end and displayed using a mobile app or JavaScript JSON and XML are widely used semi-structured data models Database System Concepts-7th Edition 8.3 ©Silberscha乜，Korth and SudarshanDatabase System Concepts - 7 8.3 ©Silberschatz, Korth and Sudarshan th Edition Semi-Structured Data ▪ Many applications require storage of complex data, whose schema changes often ▪ The relational model’s requirement of atomic data types may be an overkill • E.g., storing set of interests as a set-valued attribute of a user profile may be simpler than normalizing it ▪ Data exchange can benefit greatly from semi-structured data • Exchange can be between applications, or between back-end and front-end of an application • Web-services are widely used today, with complex data fetched to the front-end and displayed using a mobile app or JavaScript ▪ JSON and XML are widely used semi-structured data models