Memcached
replace
command is used to replace the existing
key
value
(data value).
If The The parameters are described as follows: In the following example, we set: Key → mykey Flag → 0 Exptime → 900 (in seconds) Bytes → 10 (bytes of data storage) Value → data_value In the following example, we use the key ‘mykey’’ and store the corresponding value If the data is added successfully, the output: Output information description:
key
does not exist, the replacement fails and you will get a response
NOT_STORED
. 1.7.1. Syntax: ¶
replace
basic syntax format of the command is as follows:replace key flags exptime bytes [noreply]
value
key
:Key value
key-value
in the structure
key
used to find cached values
flags
:Can include integer parameters for key-value pairs, which clients use to store additional information about key-value pairs
exptime
:Length of time to save key-value pairs in the cache (in seconds,0 means forever)
bytes
:Number of bytes stored in the cache
noreply
(optional): this parameter tells the server that there is no need to return data
value
:The stored value (always in the second line) (which can be directly understood as
key-value
in the structure
value
) 1.7.2. Example ¶
data_value
. After execution, we replace the same
key
the value of is ‘some_other_value’ .add mykey 0 900 10
data_value
STORED
get mykey
VALUE mykey 0 10
data_value
END
replace mykey 0 900 16
some_other_value
get mykey
VALUE mykey 0 16
some_other_value
END
1.7.3. Output ¶
STORED
STORED
:Output after being saved successfully
NOT_STORED
:Output after failed to perform replacement