How many databases does redis have?
Under redis, the database is identified by an integer index rather than a database name.
By default, a client connects to database 0.
The following parameters in the redis configuration file control the total number of databases:
/etc/redis/redis.conf
In the file, there is a configuration item databases = 16 // There are 16 databases by default
REmote DIctionary Server (Redis) is a key-value storage system written by Salvatore Sanfilippo .
Redis is an open source log-type Key-Value database written in ANSI C language, abides by the BSD protocol, supports the network, can be memory-based and persistent, and provides APIs in multiple languages.
It is often called a data structure server because values can be strings, hashes, lists, sets and sorted sets ) and other types.
For more Redis-related technical articles, please visit the Redis Tutorial column to learn!
The above is the detailed content of How many databases does redis have?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
How to build the redis cluster mode
Apr 10, 2025 pm 10:15 PM
Redis cluster mode deploys Redis instances to multiple servers through sharding, improving scalability and availability. The construction steps are as follows: Create odd Redis instances with different ports; Create 3 sentinel instances, monitor Redis instances and failover; configure sentinel configuration files, add monitoring Redis instance information and failover settings; configure Redis instance configuration files, enable cluster mode and specify the cluster information file path; create nodes.conf file, containing information of each Redis instance; start the cluster, execute the create command to create a cluster and specify the number of replicas; log in to the cluster to execute the CLUSTER INFO command to verify the cluster status; make
MySQL: An Introduction to the World's Most Popular Database
Apr 12, 2025 am 12:18 AM
MySQL is an open source relational database management system, mainly used to store and retrieve data quickly and reliably. Its working principle includes client requests, query resolution, execution of queries and return results. Examples of usage include creating tables, inserting and querying data, and advanced features such as JOIN operations. Common errors involve SQL syntax, data types, and permissions, and optimization suggestions include the use of indexes, optimized queries, and partitioning of tables.
How to clear redis data
Apr 10, 2025 pm 10:06 PM
How to clear Redis data: Use the FLUSHALL command to clear all key values. Use the FLUSHDB command to clear the key value of the currently selected database. Use SELECT to switch databases, and then use FLUSHDB to clear multiple databases. Use the DEL command to delete a specific key. Use the redis-cli tool to clear the data.
How to read redis queue
Apr 10, 2025 pm 10:12 PM
To read a queue from Redis, you need to get the queue name, read the elements using the LPOP command, and process the empty queue. The specific steps are as follows: Get the queue name: name it with the prefix of "queue:" such as "queue:my-queue". Use the LPOP command: Eject the element from the head of the queue and return its value, such as LPOP queue:my-queue. Processing empty queues: If the queue is empty, LPOP returns nil, and you can check whether the queue exists before reading the element.
Why Use MySQL? Benefits and Advantages
Apr 12, 2025 am 12:17 AM
MySQL is chosen for its performance, reliability, ease of use, and community support. 1.MySQL provides efficient data storage and retrieval functions, supporting multiple data types and advanced query operations. 2. Adopt client-server architecture and multiple storage engines to support transaction and query optimization. 3. Easy to use, supports a variety of operating systems and programming languages. 4. Have strong community support and provide rich resources and solutions.
How to configure Lua script execution time in centos redis
Apr 14, 2025 pm 02:12 PM
On CentOS systems, you can limit the execution time of Lua scripts by modifying Redis configuration files or using Redis commands to prevent malicious scripts from consuming too much resources. Method 1: Modify the Redis configuration file and locate the Redis configuration file: The Redis configuration file is usually located in /etc/redis/redis.conf. Edit configuration file: Open the configuration file using a text editor (such as vi or nano): sudovi/etc/redis/redis.conf Set the Lua script execution time limit: Add or modify the following lines in the configuration file to set the maximum execution time of the Lua script (unit: milliseconds)
How to use the redis command line
Apr 10, 2025 pm 10:18 PM
Use the Redis command line tool (redis-cli) to manage and operate Redis through the following steps: Connect to the server, specify the address and port. Send commands to the server using the command name and parameters. Use the HELP command to view help information for a specific command. Use the QUIT command to exit the command line tool.
How to set the redis expiration policy
Apr 10, 2025 pm 10:03 PM
There are two types of Redis data expiration strategies: periodic deletion: periodic scan to delete the expired key, which can be set through expired-time-cap-remove-count and expired-time-cap-remove-delay parameters. Lazy Deletion: Check for deletion expired keys only when keys are read or written. They can be set through lazyfree-lazy-eviction, lazyfree-lazy-expire, lazyfree-lazy-user-del parameters.
