MySQL is a widely used open source database management system that supports different kinds of databases. In this article, we will explore the different databases of MySQL.
The core of MySQL is MySQL Server, which can manage multiple databases. These databases can be independent or share a MySQL instance, each with its own data structures and tables.
In MySQL, the database is used to organize, store and manage data. Each database has its own different characteristics and uses. Several commonly used MySQL databases will be introduced below.
MySQL database is the most basic database of MySQL and it is the main component of MySQL Server. In MySQL, you can create a MySQL database by using the command line or visual tools.
MySQL database can contain multiple tables, each table has its own name and contains multiple fields. MySQL database also supports transactions, which is a method of combining multiple operations into a single operation, so that if one operation fails, all operations will be rolled back. MySQL database also supports stored procedures, which is a way to perform multiple operations in MySQL.
InnoDB is a standard storage engine of MySQL, which uses some special technologies to improve data integrity and reliability. InnoDB database can help MySQL achieve ACID transactions, which means it is atomic, consistent, isolated and durable.
InnoDB database supports row-level locks and foreign keys, and has efficient performance when handling a large number of concurrent requests. Additionally, InnoDB databases are scalable so they can be scaled up to large applications.
MyISAM is a basic storage engine of MySQL. It has efficient read performance and is suitable for applications that handle a large number of read operations. MyISAM uses table-level locks, which means it cannot perform multiple write operations at the same time, which may affect its concurrent processing capabilities.
While MyISAM has efficient performance on reads, it is less fault tolerant and therefore has a higher risk of data loss when performing write operations.
Memory database is a temporary storage engine of MySQL. It stores data in memory, so it has very fast read and write operations. Memory databases are suitable for storing temporary data so that they can be accessed faster, but all memory data will be cleared when the server is shut down or restarted.
In addition, the storage of the Memory database is volatile, so if a system failure or downtime occurs, all data stored in the memory may be lost.
Summary:
MySQL has a variety of databases, each with its own different characteristics and uses. Which database to choose depends on the needs of the application and the type of operations. When selecting a database, you need to carefully consider its performance, fault tolerance, concurrency and other factors to ensure that MySQL can effectively meet the needs of your application.
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