I recently got to know Redis, integrated it into my project and now I am facing the following use case.

My question in short:
Which data type can I use to get all entries sorted AND to be able to overwrite single entries?

My question in long:
I have a huge amount of point cloud models that I want to store and work with via Redis. My point cloud model consists of three things:

• Unique id (stays the same)
• Point Cloud as a string (changes over time)
• Priority as an integer (changes over time)

Basically I would like to be able to do only two things with Redis. However, if I understand the documentation correctly, these are seen as benefits of two different data types, so I can't find a data type that exactly fits my use case. I hope, however, that I am wrong about this and that someone here can help me.

Use case:

• Get quick all models, all already sorted
• Overwrite/update a specific model

Sorted Sets

Advantage

• Get all entries in sorted order

• my model property Priority can be used here as a score, which determines the order.
  

Disadvantage

• No possibility to access a special value via a key and overwrite it.
  

Hashes:

Advantage

• Overwrite specific entry via Key > Field
• Get all entries via Key
  

Disadvantage

• No sorting

CodePudding user response：

I would suggest to just use two distinct data types:

• a hash with all the properties of your model, with the exception of the priority;
• a sorted set which allows to easily sort your collection and deal with the scores / priorities.

You could then link the two by storing each hash key (or a distinctive value which allows to reconstruct the final hash key) as the related sorted set member.

For example:

> HSET point-cloud:123 foo bar baz suppiej
> ZADD point-clouds-by-priority 42 point-cloud:123

You will keep all the advantages you mentioned, with no disadvantages at all.