> ## 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.

# JSON.MERGE

> Merge JSON values.

Use `JSON.MERGE` to merge a JSON value into a document at a path, following the JSON Merge Patch semantics of RFC 7386.

Objects are merged recursively: keys in the patch replace or create the matching keys in the target, keys set to `null` delete them, and any value that is not an object, arrays included, replaces the target outright instead of being merged element by element. The parent must already exist: merging into a missing child of an existing object creates it, but intermediate levels are not built along the way, and a key that does not exist yet can only be created by merging at the root.

This is the command for partial updates of an object, where [`JSON.SET`](/docs/redis/commands/json/json-set) would replace the whole branch: one call can change a few fields, delete another, and leave the rest of the document untouched.

## Syntax

```redis theme={"system"}
JSON.MERGE <key> <path> <value>
```

## Arguments

| Argument | Required | Repeatable | Description                                  |
| -------- | -------- | ---------- | -------------------------------------------- |
| `key`    | Yes      | No         | JSON document key.                           |
| `path`   | Yes      | No         | Path to merge into.                          |
| `value`  | Yes      | No         | Valid JSON value containing the merge patch. |

## Important points

* Raw TCP examples pass JSON values as valid JSON text. Typed Upstash SDK helpers serialize native objects and values for you.
* Paths beginning with `$` use JSONPath and can match multiple values, so many JSON commands return an array of per-match results.

## 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    | Simple string `OK` |
| RESP3    | Simple string `OK` |

<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"}
    JSON.MERGE profile $ '{"active":true}'
    ```
  </Accordion>

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

    const redis = Redis.fromEnv();

    await redis.json.merge("key", "$.path.to.value", {"new": "value"})
    ```
  </Accordion>

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

    redis = Redis.from_env()
    result = redis.json().merge("profile", "$", {"active": True})
    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.call("JSON.MERGE", "profile", "$", "{\"active\":true}");
    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.json.merge("profile", "$", { active: true });
    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.json().merge("profile", "$", {"active": True})
    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.JSONMerge(context.Background(), "profile", "$", `{"active":true}`).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.JedisPooled;

    try (JedisPooled jedis = new JedisPooled(new URI(System.getenv("REDIS_URL")))) {
      Object result = jedis.jsonMerge("profile", new redis.clients.jedis.json.Path("$"), java.util.Map.of("active", true));
      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("JSON.MERGE");
        command.arg("profile");
        command.arg("$");
        command.arg("{\"active\":true}");
        let result: redis::Value = command.query(&mut connection)?;
        println!("{result:?}");
        Ok(())
    }
    ```
  </Accordion>
</AccordionGroup>


## Related topics

- [JSON.MERGE](/docs/redis/sdks/py/commands/json/merge.md)
- [Changelog](/docs/redis/overall/changelog.md)
- [Document Updates](/docs/redis/search/document-updates.md)
- [Update](/docs/vector/sdks/py/example_calls/update.md)