Learn Basic Redis Commands

Redis is an in-memory database that persists on disk. The data model is key-value, but many different kinds of values are supported: Strings, Lists, Sets, Sorted Sets, Hashes, HyperLogLogs, Bitmaps.

We wrote a few guides on Redis in past few months. You can find them in our Redis blog category here. Today we will show you some basic Redis Commands that will be helpful when working on Redis.

• Start redis with the related configuration file from SSH
  redis-server /path/redis.conf
• Open a redis prompt from SSH
  redis-cli

Redis Log Location /var/log/
Redis Log File – redis.log or redis_portnumber.log

• Check configuration loaded on redis-server
  cat /var/log/redis_6379.log | grep Configuration
  The output will be as the following image.
  Here you can check timings when you stared redis-server and see if logs have the “Configuration Loaded”. If configuration loaded
  You can use nano to manually view full log.
  nano /var/log/redis_6379.log

Below Commands Should be run inside redis-cli

• Check Redis Server status
  PING
  The output should be ‘PONG’ if server status is active
• Set value in the key
  SET key value
• Get value in the key
  GET key
• Get the length of the value stored in a key
  STRLEN key
• Increment value in the key
  INCR key
• Increment the integer value of a key by the given amount
  INCRBY key increment
• Decrement the integer value of the key by one
  DECR key
• Decrement the integer value of a key by the given number
  DECRBY key decrement
• Delete key
  DEL key
• List of all active configuration variables you can change
  CONFIG GET *
• Get the value of maxmemory configuration for Redis
  CONFIG GET maxmemory
• Get the value of dbfilename
  CONFIG GET dbfilename
• Change key by issuing a “CONFIG SET” command like
  CONFIG SET timeout 500
  500 is new value
• Change the key value for maxmemory
  CONFIG SET maxmemory 4157683648
  4157683648 is new value
• Check the number of keys in the database.
  DBSIZE
• Check if a key exists
  EXISTS key
  Output will be in 0 or 1
  Here, 0 and: 1 mean false and true, respectively.
• Purge all of the keys from the database
  FLUSH DB
• Close both Redis and our telnet session
  SHUTDOWN