Redis has a database-like concept called database numbering, which allows users to isolate data by number (0-15), thereby supporting multi-tenancy, improving performance and security.
Does Redis have the concept of a database?
Answer: Yes
Detailed explanation:
Redis is a key-value store database that uses memory as the primary storage medium. Unlike relational databases, Redis does not have a database concept in the traditional sense. However, it has a similar concept called database numbering.
Database number:
Redis allows users to isolate data by database number. Each Redis instance can have up to 16 databases. These databases are numbered from 0 to 15, and by default, Redis uses database number 0.
Use database number:
You can use the following command to select a specific database number:
<code>SELECT <database_number></code>
For example, to select database number 5, you can use The following command:
<code>SELECT 5</code>
Data isolation:
Although the database number provides the ability to isolate data, it should be noted that the data in Redis is not completely isolated. . For example, a key's time-to-live (TTL) is shared across all databases. This means that if the TTL of a key is set in database 5, it will also affect the data with the same key in database 0.
Advantages:
Using database numbers brings the following benefits:
Disadvantages:
There are also some disadvantages to using database numbers:
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