Should I increment multipule fields of key in a single command?

Question

I have created key in redis as follows.

hmset mykey field1 1 field2 2
OK

//checked with command
hgetall mykey
1) "field1"
2) "1"
3) "field2"
4) "2"

result is ok, and working fine. Now I want to increment both value in a single command like

hincrby mykey field1 1 field2 1

is it possible?

Answer 1

No - HINCRBY does not support this type of use. If your motivation is to ensure the atomicity of the two increments, use MULTI/EXEC or a server-side Lua script (see the EVAL command).

Here's how do address the original question to ensure atomicity:

MULTI
HSET mykey field1 1
HSET mykey field2 2
EXEC

For 2nd question (in the comments - "set only if greater then"), the following script should be EVALed with these parameters 1 <keyname> <value>:

local curr = tonumber(redis.call("GET", KEYS[1]))
if type(curr) == "number" and curr < tonumber(ARGV[1]) then
    redis.call("SET", KEYS[1], ARGV[1])
    return "OK"
end