How to atomically delete keys matching a pattern using Redis

Execute in bash:

redis-cli KEYS "prefix:*" | xargs redis-cli DEL

UPDATE

Ok, i understood. What about this way: store current additional incremental prefix and add it to all your keys. For example:

You have values like this:

prefix_prefix_actuall = 2
prefix:2:1 = 4
prefix:2:2 = 10

When you need to purge data, you change prefix_actuall first (for example set prefix_prefix_actuall = 3), so your application will write new data to keys prefix:3:1 and prefix:3:2. Then you can safely take old values from prefix:2:1 and prefix:2:2 and purge old keys.

Starting with redis 2.6.0, you can run lua scripts, which execute atomically. I have never written one, but I think it would look something like this

EVAL "return redis.call('del', unpack(redis.call('keys', ARGV[1])))" 0 prefix:[YOUR_PREFIX e.g delete_me_*]

Warning: As the Redis document says, because of performance maters, keys command should not use for regular operations in production, this command is intended for debugging and special operations. read more

See the EVAL documentation.