Redis Basics

Redis is an open source (BSD licensed), in-memory data structure store, used as a database, cache and message broker.

Redis is an in-memory data structure store, used as a database, cache and message broker.

SET key value Set the string value of a key. e.g. SET mykey "Hello"
GET key Get the value of a key. e.g. GET mykey
DEL key Delete a key. e.g. DEL mykey
EXISTS key Determine if a key exists. e.g. EXISTS mykey
MSET key value [key value ...] Set multiple keys to multiple values. e.g. MSET key1 "Hello" key2 "World"
MGET key [key ...] Get the values of all the given keys. e.g. MGET key1 key2
RANGE key start stop Get a substring of the string stored at a key. e.g. RANGE mykey 0 3, RANGE mykey -2 -1
SETRANGE key offset value Overwrite part of a string at key starting at the specified offset. e.g. SETRANGE mykey 0 "Hello"

Redis configuration file is located at /etc/redis/redis.conf
Redis configuration file is divided into sections, denoted by square brackets. e.g. [section_name]
Redis configuration file is composed of simple key-value pairs. e.g. bind
Docker redis configuration file is located at /usr/local/etc/redis/redis.conf

docker run -d --name redis -p 6379:6379 redis redis-server --appendonly yes -v /Users/zhengyansheng/redis/redis.conf:/usr/local/etc/redis/redis.conf

SET name "zhengyansheng" EX 10 NX EX seconds -- Set the specified expire time, in seconds. NX -- Only set the key if it does not already exist.
SET name "zhengyansheng" PX 10000 NX PX milliseconds -- Set the specified expire time, in milliseconds.
SET name "zhengyansheng" XX XX -- Only set the key if it already exist.
SET name "zhengyansheng" GET GET -- Get the value of a key and set its value to a new one.

SADD key member [member ...] Add one or more members to a set. e.g. SADD myset "Hello"
SMEMBERS key Get all the members in a set. e.g. SMEMBERS myset
SISMEMBER key member Determine if a given value is a member of a set. e.g. SISMEMBER myset "Hello"
SREM key member [member ...] Remove one or more members from a set. e.g. SREM myset "Hello"
SUNION key [key ...] Add multiple sets. e.g. SUNION set1 set2

LPUSH key value [value ...] Prepend one or multiple values to a list. e.g. LPUSH mylist "World"
RPUSH key value [value ...] Append one or multiple values to a list. e.g. RPUSH mylist "World"
LRANGE key start stop Get a range of elements from a list. e.g. LRANGE mylist 0 3
LPOP key Remove and get the first element in a list. e.g. LPOP mylist
RPOP key Remove and get the last element in a list. e.g. RPOP mylist
LLEN key Get the length of a list. e.g. LLEN mylist
LREM key count value Remove elements from a list. e.g. LREM mylist 2 "Hello"
LSET key index value Set the value of an element in a list by its index. e.g. LSET mylist 0 "Hello"
LTRIM key start stop Trim a list to the specified range. e.g. LTRIM mylist 0 2

HSET key field value Set the string value of a hash field. e.g. HSET myhash field1 "Hello"
HGET key field Get the value of a hash field. e.g. HGET myhash field1
HGETALL key Get all the fields and values in a hash. e.g. HGETALL myhash
HDEL key field [field ...] Delete one or more hash fields. e.g. HDEL myhash field1
HEXISTS key field Determine if a hash field exists. e.g. HEXISTS myhash field1
HINCRBY key field increment Increment the integer value of a hash field by the given number. e.g. HINCRBY myhash field1 5
HKEYS key Get all the fields in a hash. e.g. HKEYS myhash
HLEN key Get the number of fields in a hash. e.g. HLEN myhash
HMGET key field [field ...] Get the values of all the given hash fields. e.g. HMGET myhash field1 field2
HMSET key field value [field value ...] Set multiple hash fields to multiple values. e.g. HMSET myhash field1 "Hello" field2 "World"
HSETNX key field value Set the value of a hash field, only if the field does not exist. e.g. HSETNX myhash field1 "Hello"
HVALS key Get all the values in a hash. e.g. HVALS myhash