Redis provides multiple ways to read the cache: Direct read: Use the GET command to retrieve a single key-value pair. Iterate over keys: Use the SCAN command to iterate over all keys and get the values. Listen for keys: Use the SUBSCRIBE command to listen for key updates. Pipeline command: Read multiple key-value pairs at the same time to reduce the number of network round-trips. Atomic operations: Use the MULTI and EXEC commands to read multiple key-value pairs atomically.
Redis reads the latest cache
Redis is a popular in-memory database known for its high performance and Known for its flexible data structures. Redis provides multiple methods of reading the cache to meet different application needs.
Read directly
The most direct method is to use theGET
command to directly read a single key-value pair:
GET key
This command will return the value corresponding to keykey
.
Traverse keys
To iterate over all keys and read their latest values, you can use theSCAN
command:
SCAN 0
TheSCAN
command will return a cursor and a set of keys. You can reuse the cursor to get the next set of keys until the returned cursor is0
.
Listen for keys
To listen for keys and read their latest values, you can use theSUBSCRIBE
command:
SUBSCRIBE channel
When When a key is updated, the Redis server will push a message to the specified channel.
Pipeline command
If you need to read multiple key-value pairs at the same time, you can use the pipeline command. Pipeline commands reduce the number of network round trips by packaging multiple commands into a single request.
PIPELINE GET key1 GET key2 EXEC
Atomic operations
To read multiple key-value pairs atomically, you can use theMULTI
andEXEC
commands :
MULTI GET key1 GET key2 EXEC
MULTI
command starts a transaction,EXEC
command commits the transaction and returns the result.
Choose the appropriate method
Choosing the most appropriate read method depends on the specific requirements of the application. For small data sets, direct reading may be sufficient. For large data sets or when real-time updates are required, traversing keys, listening keys, or pipe commands are better choices.
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