Question

The basic setup is this:

SET foo bar
SET baz foo

Is something like this possible in a single statement?

GET GET baz
"bar"

thanks

Answer 1

You can't do it using basic redis API.

I can see two options for you:

do it yourself in whatever programming language you're using with redis;
do it with a lua script.

Here is a very simple lua script example, doing what you want:

eval "return redis.call('get', redis.call('get', KEYS[1]))" 1 baz

N.B.: You can only use this script with standalone redis installation, because it's using keys that aren't explicitly declared via the KEYS array, so it's not cluster-safe (thanx to Itamar Haber's comment).

Answer 2

虽然您无法使用Redis字符串执行此操作，但如果您使用所有＆＃34;密钥保留哈希值，那么这是可行的。和＆＃34;价值观＆＃34;代替。例如：

HSET miniredis foo bar
HSET miniredis baz foo

现在，要获取商品，您需要Lua，但由于所有内容都捆绑在一个数据结构中，因此它将是群集安全的（以可扩展性为代价）。

EVAL "return redis.call('HGET', KEYS[1], redis.call('HGET', KEYS[1], ARGV[1]))" 1 miniredis baz

当然，这仅在总有一个解除引用级别时才有效。另一个特点是自我引用的能力（即HSET miniredis minime minime）。如果需要，应该处理这些。

Is nested GET possible in Redis?

2 个答案: