How to set/get pandas.DataFrame to/from Redis?

问题:

After setting a DataFrame to redis, then getting it back, redis returns a string and I can't figure out a way to convert this str to a DataFrame.

How can I do these two appropriately?

回答1:

set:

redisConn.set("key", df.to_msgpack(compress='zlib'))

get:

pd.read_msgpack(redisConn.get("key"))

回答2:

I couldn't use msgpack because of Decimal objects in my dataframe. Intead I combined pickle and zlib together like this, assuming a dataframe df and a local instance of redis:

import pickle
import redis
import zlib

EXPIRATION_SECONDS = 600

r = redis.StrictRedis(host='localhost', port=6379, db=0)

# Set
r.setex("key", EXPIRATION_SECONDS, zlib.compress( pickle.dumps(df)))

# Get
rehydrated_df = pickle.loads(zlib.decompress(r.get("key")))

There isn't anything anything dataframe specific about this.

Caveats

• the other answer using msgpack is better -- use it if it works for you
• pickling can be dangerous -- your Redis server needs to be secure or you're asking for trouble