全部命令如下：
127.0.0.1:6379> help @string
APPEND key value
summary: Append a value to a key
since: 2.0.0
DECR key
summary: Decrement the integer value of a key by one
since: 1.0.0
DECRBY key decrement
summary: Decrement the integer value of a key by the given number
since: 1.0.0
GET key
summary: Get the value of a key
since: 1.0.0
GETDEL key
summary: Get the value of a key and delete the key
since: 6.2.0
GETEX key [EX seconds|PX milliseconds|EXAT unix-time-seconds|PXAT unix-time-milliseconds|PERSIST]
summary: Get the value of a key and optionally set its expiration
since: 6.2.0
GETRANGE key start end
summary: Get a substring of the string stored at a key
since: 2.4.0
GETSET key value
summary: Set the string value of a key and return its old value
since: 1.0.0
INCR key
summary: Increment the integer value of a key by one
since: 1.0.0
INCRBY key increment
summary: Increment the integer value of a key by the given amount
since: 1.0.0
INCRBYFLOAT key increment
summary: Increment the float value of a key by the given amount
since: 2.6.0
LCS key1 key2 [LEN] [IDX] [MINMATCHLEN len] [WITHMATCHLEN]
summary: Find longest common substring
since: 7.0.0
MGET key [key ...]
summary: Get the values of all the given keys
since: 1.0.0
MSET key value [key value ...]
summary: Set multiple keys to multiple values
since: 1.0.1
MSETNX key value [key value ...]
summary: Set multiple keys to multiple values, only if none of the keys exist
since: 1.0.1
PSETEX key milliseconds value
summary: Set the value and expiration in milliseconds of a key
since: 2.6.0
SET key value [NX|XX] [GET] [EX seconds|PX milliseconds|EXAT unix-time-seconds|PXAT unix-time-milliseconds|KEEPTTL]
summary: Set the string value of a key
since: 1.0.0
SETEX key seconds value
summary: Set the value and expiration of a key
since: 2.0.0
SETNX key value
summary: Set the value of a key, only if the key does not exist
since: 1.0.0
SETRANGE key offset value
summary: Overwrite part of a string at key starting at the specified offset
since: 2.2.0
STRLEN key
summary: Get the length of the value stored in a key
since: 2.2.0
SUBSTR key start end
summary: Get a substring of the string stored at a key
since: 1.0.0
示例如下：
hset ：hset key field value，将field:value构成的键值对放入key对应的hash表中。
hmset ：hmset key field1 value1 field2 value2...批量将键值对放入key对应的hash表中。
hget：hget key field，取出key对应的hash表中某个field对应的value。
127.0.0.1:6379> hset jack name testJack
(integer) 1
127.0.0.1:6379> hmset jack salary 1000 city shanghai
OK
127.0.0.1:6379> hget jack name
"testJack"
hkeys ：hkeys key，列出key对应的hash表中所有的fields。
hvals ：hvals key，列出key对应的hash表中所有的value。
hgetall：hgetall key，列出key对应的hash表中所有的field和value
127.0.0.1:6379> hkeys jack
1) "name"
2) "salary"
3) "city"
127.0.0.1:6379> hvals jack
1) "testJack"
2) "1000"
3) "shanghai"
127.0.0.1:6379> hgetall jack
1) "name"
2) "testJack"
3) "salary"
4) "1000"
5) "city"
6) "shanghai"
hincrbyfloat：hincrbyfloat key field value。将key对应的hash表中field对应的值与value进行浮点运算
127.0.0.1:6379> HINCRBYFLOAT jack age -1.2
"19.3"
127.0.0.1:6379> hgetall jack
1) "name"
2) "testJack"
3) "salary"
4) "1000"
5) "city"
6) "shanghai"
7) "age"
8) "19.3"
redis中的hash表可以抽象为一个对象，通过hgetall可以取出该对象所有数据。