What data does redis cache?
Redis’ cache data types include: string, hash, list, set, ordered set, geographical location, stream, HyperLogLog, Bitmap, modular data types (such as RedisJSON, RedisGraph, RedisTimeSeries).
Redis cached data types
Redis is a high-performance key-value database with powerful caching capabilities make it ideal for a variety of application scenarios. For the data types of Redis cache, we can mainly divide them into the following categories:
1. String (String)
String is the most basic data Type that can store any text, numeric, or binary data.
2. Hash
Hash is a data type of key-value pair structure, in which each key is associated with a value. It is very suitable for storing objects or structured data.
3. List (List)
A list is an ordered sequence data type in which the elements are arranged in insertion order. It provides fast insertion, deletion and access operations.
4. Set
A set is an unordered collection of non-repeating elements. It can efficiently perform set operations such as intersection, union and complement.
5. Sorted Set
An ordered set is a special set whose elements are sorted according to a specific score. It supports range queries and sorting operations on scores.
6. Geographical location (Geo)
The geographical location type is used to store and operate geospatial data, such as latitude and longitude coordinates. It supports distance queries and range searches for geographical locations.
7. Stream
Stream is an infinite, append-based data type used to store time series data. It provides efficient event ingestion and streaming.
8. HyperLogLog
HyperLogLog is an approximate cardinality estimation data type used to count the number of unique elements in large data sets. It can process large amounts of data efficiently, but at the expense of accuracy.
9. Bitmap
Bitmap is a space-efficient data type used to represent an array of Boolean values. It's great for tracking status, counts, or collection membership.
10. Modular data types
In addition to the above core data types, Redis also supports various modular data types, such as RedisJSON, RedisGraph and RedisTimeSeries. These modules provide additional functionality such as JSON document storage, graph databases, and time series management.
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