redis data types and structural characteristics
Redis supports multiple data types, each type has a unique structure: string: byte array, which can append, modify and obtain range data. List: An ordered byte array sequence that can add/pop elements and get/modify index elements. Hash: A collection of key-value pairs, which can set/get/delete key-value pairs and obtain all keys/values. Set: An unordered, unique collection of elements, which can add/remove elements, obtain all elements, and find intersection/union. Ordered collection: An ordered collection of key-value pairs, which can add/delete key-value pairs, obtain key scores, and obtain range data of specified scores or keys.
Redis data types and their structural characteristics
Redis is an in-memory database that supports multiple data types , each data type has its unique structural characteristics.
String (String)
- Structure: It consists of a byte array and can store any data.
-
Features:
- Data can be appended through the APPEND command.
- Data can be modified through the SETRANGE command.
- You can obtain data in the specified range through the GETRANGE command.
List
- Structure: an ordered sequence of byte arrays, each element can be Arbitrary data.
-
Features:
- Elements can be added to the beginning/end of the list through the LPUSH/RPUSH command.
- You can pop elements from the beginning/end of the list through the LPOP/RPOP command.
- You can obtain/modify elements in the list through the LINDEX/LSET command.
Hash
- Structure: a collection of key-value pairs, where the key is a string, The value can be any data.
-
Features:
- You can set/get key-value pairs through the HSET/HGET command.
- Key-value pairs can be deleted through the HDEL command.
- All keys/values can be obtained through the HKEYS/HVALS command.
Set
- Structure: an unordered, unique set of elements.
-
Features:
- Elements can be added/removed through the SADD/SREM command.
- You can get all elements in the collection through the SMEMBERS command.
- You can use the SINTER/SUNION command to find the intersection/union.
Sorted Set
- Structure: an ordered set of key-value pairs, where the key is a string and the value is a floating point fraction.
-
Features:
- You can add/delete key-value pairs through the ZADD/ZREM command.
- The score of a key can be obtained through the ZSCORE command.
- You can get the scores or keys in the specified range through the ZRANGE/ZREVRANGE command.
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