Redis Data type: Strings

String is the simplest data type, a key corresponding to a value,string type is binary safe, Redis string can contain any data,

For example, JPG images or serialized objects.

Set Method:

Sets the value of the key corresponding to string type value, for example, we add a

The key-value pair for the name=xiaoming.

[Email protected] bin]# redis-cli-h 127.0.0.1-p 6379-a lh801309
127.0.0.1:6379> Set Name Xiaoming
Ok
127.0.0.1:6379> Get Name
"Xiaoming"
127.0.0.1:6379>

If the same key in the set is overwritten, what if you do not want to overwrite it?

Can be used with the Setnx method, if no addition exists, there is a return of 0

127.0.0.1:6379> setnx name Xiaohong
(integer) 0

Setex method: Specifies the validity period of the set key:

127.0.0.1:6379> Setex age 10 10
Ok
127.0.0.1:6379> Get Age
"10"
127.0.0.1:6379> Get Age
(nil)

SetRange method: Replacing substrings

127.0.0.1:6379> set mail [email protected]
Ok
127.0.0.1:6379> SETRANGE Mail 4 @gmail. com
(integer) 14
127.0.0.1:6379> Get Mail
"[Email protected] @gmail. com"
127.0.0.1:6379>

Mset Method: Bulk Insert

127.0.0.1:6379> MSET key1 1 key2 2 Key3 3
Ok
127.0.0.1:6379> Get Key1
"1"
127.0.0.1:6379> Get Key2
"2"
127.0.0.1:6379> Get Key3
"3"

Msetnx set the value of multiple keys at once, successful return OK means all values are set,

Failure to return 0 means that no value is set, but does not overwrite the existing key

127.0.0.1:6379> msetnx Key4 4 key5 5 Key3 0
(integer) 0
127.0.0.1:6379> Get Key4
(nil)

As long as one does not succeed, it returns 0 because Key3 already exists.

Getset method: Get the old value and set the new value

127.0.0.1:6379> Get Key1
"1"
127.0.0.1:6379> Getset Key1 100
"1"
127.0.0.1:6379> Get Key1
"100"

GetRange method: Gets the specified substring

127.0.0.1:6379> Get Mail
"[Email protected] @gmail. com"
127.0.0.1:6379> GETRANGE Mail 0 6
"[Email protected] @gm"

Mget method: Bulk Fetch

127.0.0.1:6379> mget key1 Key2 Key3
1) "100"
2) "2"
3) "3"

Incr method: Perform a Gaga operation on the value of key and return the new value

127.0.0.1:6379> Get Key1
"100"
127.0.0.1:6379> INCR Key1
(integer) 101
127.0.0.1:6379> INCR Key1
(integer) 102

Incrby method: With INCR, add the specified value, key does not exist when you set key back,

and thinks the original value is 0.

127.0.0.1:6379> Get Key1
"102"
127.0.0.1:6379> Incrby Key1 5
(integer) 107
Setting a positive number is plus, setting a negative value is minus

Decr method: The value of key is reduced and reduced.

Decrby method: Similar to DECR, minus the specified value

Append method: Append value to the specified key

127.0.0.1:6379> Get Mail
"[Email protected] @gmail. com"
127.0.0.1:6379> Append mail. Net
(integer) 18
127.0.0.1:6379> Get Mail
"[Email protected] @gmail. Com.net"
127.0.0.1:6379>

Strlen gets the value of the specified key

127.0.0.1:6379> Get Mail
"[Email protected] @gmail. Com.net"
127.0.0.1:6379> STRLEN Mail
(integer) 18

Redis Data type: Strings