> ## Documentation Index
> Fetch the complete documentation index at: https://upstash.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# ZDIFF

> Get sorted set difference.

Use `ZDIFF` to get the members of the first sorted set that do not appear in any of the others.

`<numkeys>` states how many keys follow. Scores come from the first set and are returned only when `WITHSCORES` is given, and the result keeps the ordering of that set. Keys that do not exist count as empty.

The result is computed on each call and not stored; use [`ZDIFFSTORE`](/docs/redis/commands/sorted-set/zdiffstore) to keep it. This is how you exclude one group from a ranking, for example dropping already-seen items from a scored feed.

## Syntax

```redis theme={"system"}
ZDIFF <numkeys> <key> [<key> ...] [WITHSCORES]
```

## Arguments

| Argument     | Required | Repeatable | Description                          |
| ------------ | -------- | ---------- | ------------------------------------ |
| `<numkeys>`  | Yes      | No         | Number of key arguments that follow. |
| `<key>`      | Yes      | Yes        | Redis key targeted by the command.   |
| `WITHSCORES` | No       | No         | Include sorted-set scores.           |

## Important points

* `numkeys` must equal the number of key arguments that immediately follow it.
* Pair-based results may be flattened into one alternating array in RESP2 while RESP3 preserves nested pairs or a map.
* RESP2 represents floating-point reply values as bulk strings; RESP3 may use native double replies. Client libraries commonly decode either form to a language number.

## Response

The reply reports the result of the operation. Error replies have the same shape in RESP2 and RESP3 and are surfaced as exceptions by the SDKs below.

| Protocol | Reply                                                              |
| -------- | ------------------------------------------------------------------ |
| RESP2    | Array of members, or flat member/score array with `WITHSCORES`     |
| RESP3    | Array of members, or array of member/score pairs with `WITHSCORES` |

<Note>
  Client libraries often decode bulk strings, maps, sets, and numeric strings into language-native values. The table describes the Redis wire reply.
</Note>

## Examples

TCP examples use the TLS `REDIS_URL` from the Upstash console. REST examples use `UPSTASH_REDIS_REST_URL` and `UPSTASH_REDIS_REST_TOKEN`.

<AccordionGroup>
  <Accordion title="Redis CLI" icon="terminal">
    ```bash theme={"system"}
    ZDIFF 1 my-key
    ```
  </Accordion>

  <Accordion title="@upstash/redis" icon="node-js" iconType="brands">
    <Note>
      This command is not supported yet in `@upstash/redis`.
    </Note>
  </Accordion>

  <Accordion title="upstash_redis" icon="python" iconType="brands">
    ```python theme={"system"}
    from upstash_redis import Redis

    redis = Redis.from_env()
    result = redis.zdiff(["my-key"])
    print(result)
    ```
  </Accordion>

  <Accordion title="ioredis" icon="node-js" iconType="brands">
    ```ts theme={"system"}
    import Redis from "ioredis";

    const redis = new Redis(process.env.REDIS_URL!);
    const result = await redis.zdiff("1", "my-key");
    console.log(result);
    ```
  </Accordion>

  <Accordion title="node-redis" icon="node-js" iconType="brands">
    ```ts theme={"system"}
    import { createClient } from "redis";

    const client = await createClient({ url: process.env.REDIS_URL })
      .on("error", console.error)
      .connect();
    const result = await client.zDiff("my-key");
    console.log(result);
    ```
  </Accordion>

  <Accordion title="redis-py" icon="python" iconType="brands">
    ```python theme={"system"}
    import os
    import redis

    client = redis.from_url(os.environ["REDIS_URL"])
    result = client.zdiff(["my-key"])
    print(result)
    ```
  </Accordion>

  <Accordion title="go-redis" icon="golang" iconType="brands">
    ```go theme={"system"}
    package main

    import (
        "context"
        "fmt"
        "os"

        "github.com/redis/go-redis/v9"
    )

    func main() {
        opts, err := redis.ParseURL(os.Getenv("REDIS_URL"))
        if err != nil {
            panic(err)
        }
        client := redis.NewClient(opts)
        result, err := client.ZDiff(context.Background(), "my-key").Result()
        if err != nil {
            panic(err)
        }
        fmt.Println(result)
    }
    ```
  </Accordion>

  <Accordion title="jedis" icon="java" iconType="brands">
    ```java theme={"system"}
    import java.net.URI;

    import redis.clients.jedis.Jedis;

    try (Jedis jedis = new Jedis(new URI(System.getenv("REDIS_URL")))) {
      Object result = jedis.zdiff("my-key");
      System.out.println(result);
    }
    ```
  </Accordion>

  <Accordion title="redis-rs" icon="rust" iconType="brands">
    ```rust theme={"system"}
    fn main() -> redis::RedisResult<()> {
        let url = std::env::var("REDIS_URL").expect("REDIS_URL is not set");
        let client = redis::Client::open(url)?;
        let mut connection = client.get_connection()?;

        let mut command = redis::cmd("ZDIFF");
        command.arg("1");
        command.arg("my-key");
        let result: redis::Value = command.query(&mut connection)?;
        println!("{result:?}");
        Ok(())
    }
    ```
  </Accordion>
</AccordionGroup>


## Related topics

- [ZDIFF](/docs/redis/sdks/py/commands/zset/zdiff.md)
- [ZDIFFSTORE](/docs/redis/commands/sorted-set/zdiffstore.md)
- [Overview](/docs/redis/sdks/py/commands/overview.md)