> ## Documentation Index
> Fetch the complete documentation index at: https://upstash-redis-1-18.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# ARINSERT

> Append values to an array.

Use `ARINSERT` to append one or more values to the end of an array.

Each array keeps an append cursor holding the last index written by an append, so `ARINSERT` does not need to look up where the data ends: the first value goes to the slot after the cursor, the rest follow it, and the cursor moves to the last one. The reply is the index that last value received, which is what a producer records to point at what it just wrote.

Because the cursor is separate from the contents, appending is unaffected by deletions: freeing slots with [`ARDEL`](/redis/commands/array/ardel) never causes a later append to reuse an index. Use [`ARSEEK`](/redis/commands/array/arseek) to move the cursor deliberately and [`ARNEXT`](/redis/commands/array/arnext) to read where the next append would land.

See the [array command overview](/redis/commands/array/overview) for the data model these commands share.

## Syntax

```redis theme={null}
ARINSERT <key> <value> [<value> ...]
```

## Arguments

| Argument  | Required | Repeatable | Description                                                   |
| --------- | -------- | ---------- | ------------------------------------------------------------- |
| `<key>`   | Yes      | No         | Array key targeted by the command.                            |
| `<value>` | Yes      | Yes        | Value to append. Repeat to append several values in one call. |

## Important points

* The reply is the index of the last value written, not the number of values written.
* Appending past the highest supported index returns `ERR insert index overflow`.

## 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    | Integer, or bulk string when the index exceeds the signed 64-bit range |
| RESP3    | Integer, or Big number when the index exceeds the signed 64-bit range  |

<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={null}
    ARINSERT my-array hello world
    ```
  </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">
    <Note>
      This command is not supported yet in `upstash_redis`.
    </Note>
  </Accordion>

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

    const redis = new Redis(process.env.REDIS_URL!);
    const result = await redis.arinsert("my-array", "hello", "world");
    console.log(result);
    ```
  </Accordion>

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

    const client = await createClient({ url: process.env.REDIS_URL })
      .on("error", console.error)
      .connect();
    const result = await client.arInsert("my-array", ["hello", "world"]);
    console.log(result);
    ```
  </Accordion>

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

    client = redis.from_url(os.environ["REDIS_URL"])
    result = client.arinsert("my-array", "hello", "world")
    print(result)
    ```
  </Accordion>

  <Accordion title="go-redis" icon="golang" iconType="brands">
    ```go theme={null}
    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.ARInsert(context.Background(), "my-array", "hello", "world").Result()
        if err != nil {
            panic(err)
        }
        fmt.Println(result)
    }
    ```
  </Accordion>

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

    import redis.clients.jedis.Jedis;

    try (Jedis jedis = new Jedis(new URI(System.getenv("REDIS_URL")))) {
      Object result = jedis.arinsert("my-array", "hello", "world");
      System.out.println(result);
    }
    ```
  </Accordion>

  <Accordion title="redis-rs" icon="rust" iconType="brands">
    ```rust theme={null}
    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("ARINSERT");
        command.arg("my-array");
        command.arg("hello");
        command.arg("world");
        let result: redis::Value = command.query(&mut connection)?;
        println!("{result:?}");
        Ok(())
    }
    ```
  </Accordion>
</AccordionGroup>