redis theory
A, NoSQL Profile (Not Only SQL)
1. NoSQL refers to non-relational databases, is the generic term for a database management system different from traditional relational databases, is web2.0 era of massive data NoSQL product of birth
2. Features:
(1) does not support SQL syntax
NoSQL world without a common language, each NoSQL database has its own syntax, as well as good business scene
(2) a high performance read
NoSQL databases have very high read and write performance, especially in the huge amounts of data, its performance is very good
(3) flexible data model
NoSQL storage mode is very flexible, can be json document storage, key-value pair (key value) or other means
Two, Redis Introduction
1. Redis is developed by the Italians a memory cache database, is a high-performance key-value pair (key value) stored in the database. Redis full name: Remote DictionaryServer (Remote Data Service), written in C, and to the memory as a data storage medium, it is very efficient to read and write data (in memory as a data storage medium)
2. Redis features:
(1) persistent support Redis data, data in memory can be saved to disk, restart time can be used again.
(2) Redis not support a simple key-value data types, while also divided value list, set, zset, hash and other stored data structure.
(3) Since Redis fast exchange data, in a server used to store some of the data retrieved frequently improve efficiency.