MHGETALL command to get multiple fields and values from multiple hashes

[Bessonov]

Hello,

I think it can save network traffic between client and server and make queries convenient and faster. My use case:

HMSET user:1 name User1
HMSET user:2 name User2
HMSET user:3 name User3

And now get all three users with custom delmiter between hashes (inevitably?):

MHGETALL #delimiter# user:1 user:2 user:3

1. name
2. User1
3. #delimiter#
4. name
5. User2
6. #delimiter#
7. name
8. User3

Best regards

Anton

[pietern]

This will not be implemented because it requires all keys to be available on a single server, and is therefore not well suited in a distributed environment. We avoid to add commands that have this characteristic. You can achieve the same result using a MULTI/EXEC block with HGETALL commands. While this does result in some extra bytes on the wire, you'll find that it is almost as fast as a native command when the group of commands is sent to Redis in a pipelined fashion.

Cheers,
Pieter

[antirez]

Also note that a Redis Lua script can implement this without issues. Scripting is available in Redis unstable and will be available into 2.6 stable in the future.

[Bessonov]

Thanks for the info!