What is a database instance
A database instance is a program, a layer of data management software located between the user and the operating system, and a channel for accessing the database; the user can perform any operation on the data in the database, including data definition, data query, Data maintenance, database operation control, etc. are all performed under the database instance. Applications can only deal with the database through the database instance.
The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.
1. Database (Database)
A collection of physical operating system files or disk data blocks
such as data files, index files, and structure files.
Not all database systems are file-based, and there are also forms that directly write data to data storage.
2. Database Instance
Instance refers to a series of processes in the operating system and the memory blocks allocated for these processes.
A database instance is a program, a layer of data management software located between the user and the operating system.
The database instance is the channel for accessing the database. Any operations performed by users on the data in the database, including data definition, data query, data maintenance, database operation control, etc., are all performed under the database instance. Applications can only deal with the database through the database instance.
Generally speaking, one database instance corresponds to one database.
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