Can redis replace mysql?
redis cannot replace mysql. Redis and mysql can only be complementary. Redis stores data in memory and reads it quickly, but the memory space is small. mysql is stored on the hard disk. The data is big. But reading from the hard disk is definitely slower than reading from the memory.
So the two are usually combined to solve the problem of data reading.
Introduction to the difference between mysql and redis
1. The database types of mysql and redis
mysql is a relational database. It is mainly used to store persistent data. The data is stored in the hard disk and the reading speed is slow.
redis is NOSQL, which is a non-relational database and a cache database. It stores data in the cache. The cache has fast reading speed and can greatly improve operating efficiency, but the storage time is limited
2. The operating mechanism of mysql
As a relational database with persistent storage, the relative weakness of mysql is that every time a request is made to access the database, there are I/O operations. If Access the database frequently and repeatedly.
First: It will take a lot of time to repeatedly connect to the database, resulting in too slow operating efficiency;
Second: Repeatedly accessing the database will also cause the database load to be too high, so this The concept of time cache was derived.
3. Cache
The cache is the buffer (cache) for data exchange. When the browser performs a request, it will first search in the cache. If it exists , get it; otherwise, access the database.
The advantage of caching is that the reading speed is fast
4.redis database
The redis database is a cache database used to store frequently used data. data, thus reducing the number of database accesses and improving operating efficiency.
For more Redis related knowledge, please visit theRedis usage tutorialcolumn!
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