published DBMS release redis 7.0 related to the class of NOSQL systems. Redis provides functions for storing data in the key/value format, extended by the support of structured data formats, such as lists, hashs and sets, as well as the possibility of performing Lua scripts on the side of the server. The project code supplies under the BSD license. Additional modules, which offers advanced opportunities for corporate users, such as Redisearch, Redisgraph, Redisjson, Redisml, Redisbloom, have been delivered under the Proprietary RSAL license since 2019. The development of open options for these modules under the AGPLV3 license tried to continue the project goodForm , which is recently in stagnation.
, unlike storage systems in RAM , such as Memcache, Redis provides constant storage of data on the disk and guarantees the safety of the database in case of emergency completion of the work. The initial texts of the project are distributed as part of the BSD license. Client libraries are available for most popular languages, including Perl, Python, PHP, Java, Ruby and TCL. Redis supports transactions that allow you to execute a group of commands by one step, guaranteeing consistency and sequence (teams from other requests cannot wedge), and in case of problems, allowing to roll back changes. All data is in full caching in RAM.
To control the data, commands such as an incremental/decrement, standard operations on lists and sets (association, intersection), renaming the keys, multiple sample and sorting functions are provided. Two storage modes are supported: periodic synchronization of data to disk and conducting changes on the log disk. In the second case, the complete safety of all changes is guaranteed. It is possible to organize Master-SLAVE data replication for several servers, carried out in non-closing mode. Messages of the “Publication/Subscription” messages are also available, in which a channel is created, the messages from which are distributed by subscription customers.