τJUpdate: An update language for time-varying JSON data

Time-varying JSON data are being used and exchanged in various today's application frameworks like IoT platforms, Web services, cloud computing, online social networks, and mobile systems. However, in the state-of-the-art of JSON data management, there is neither a consensual nor a standard language for updating (i.e., inserting, modifying, and deleting) temporal JSON data, like the TSQL2 or SQL:2016 languages for temporal relational data. Moreover, existing JSON-based NoSQL DBMSs (e.g., MongoDB, Couchbase, CouchDB, OrientDB, and Riak) and both commercial relational DBMSs (e.g., IBM DB2 12, Oracle 19c, and MS SQL Server 2019) and open-source ones (e.g., PostgreSQL 15, and MySQL 8.0) supporting JSON documents do not provide any facility for maintaining temporal JSON data. Also in our previously proposed temporal JSON framework, called tauJSchema, there was no feature for temporal JSON instance updates. For these reasons, we propose in this article a temporal update language, named tauJUpdate (Temporal JUpdate), for JSON data in the tauJSchema environment. We define it as a temporal extension of our previously introduced non-temporal JSON update language, named JUpdate (JSON Update). Both the syntax and the operational semantics of the data modification operations of JUpdate have been extended to support temporal aspects. tauJUpdate allows to specify temporal JSON updates in an expressive and user-friendly manner, and to efficiently execute them in the tauJSchema environment.