How to rename a hash field efficiently in Redis

Question

I can HGET mykey oldfield and store value in my application and do HSET newfield value, how can I avoid copy my value just like RENAMENX key newkey while using hash? Thanks.

Answer 1

There is no specific command to do it, but you can use a server-side Lua script to execute the following operations atomically:

• hget key field
• hsetnx key newfield value
• if successful, hdel key field

You will pay for only one roundtrip, and you can handle errors (when the new field does already exist).