BITFIELD - Upstash Documentation

Use BITFIELD to treat a string as an array of packed integers and run several operations on it in a single atomic call.

Every operation names an encoding and a bit offset. The encoding is u<bits> for unsigned integers (up to 63 bits) or i<bits> for signed integers (up to 64 bits). The offset is counted in bits from the start of the value or, when prefixed with #, in units of the encoding width, so #2 with u8 addresses the third 8-bit field. The string grows automatically with zero bits when an operation addresses an offset past its current end.

GET reads a field, SET writes one and returns its previous value, and INCRBY adds a possibly negative increment and returns the new value. OVERFLOW sets how the SET and INCRBY operations that follow it behave when a value does not fit the encoding: WRAP wraps around like modular arithmetic and is the default, SAT saturates at the minimum or maximum of the encoding, and FAIL leaves the field unchanged and returns null for that operation. The reply is an array with one entry per operation, in the order the operations were given.

Packing many small counters into a single key this way saves memory and keeps the whole update atomic, which makes it a good fit for rate limiters and compact per-user counters.

Syntax#

BITFIELD <key>  [GET <encoding> <offset> |    [OVERFLOW WRAP | SAT | FAIL]    (SET <encoding> <offset> <value> |      INCRBY <encoding> <offset> <increment>)    [GET <encoding> <offset> |      [OVERFLOW WRAP | SAT | FAIL]      (SET <encoding> <offset> <value> |        INCRBY <encoding> <offset> <increment>)      ...]]

Arguments#

Argument	Required	Repeatable	Description
`<key>`	Yes	No	Redis key targeted by the command.
`(GET <encoding> <offset> \| [OVERFLOW WRAP \| SAT \| FAIL] (SET <encoding> <offset> <value> \| INCRBY <encoding> <offset> <increment>))`	No	Yes	An operation on a field of `<encoding>` (`u<bits>` unsigned up to 63 bits, or `i<bits>` signed up to 64 bits) at `<offset>` bits, or at `#<n>` to address the n-th field of that width: `GET` reads it, `SET` writes it and returns the previous value, and `INCRBY` adds an increment and returns the new value. `OVERFLOW` sets how the `SET` and `INCRBY` operations after it handle a value that does not fit: `WRAP` wraps around (the default), `SAT` saturates at the encoding's limits, and `FAIL` leaves the field unchanged and returns null. Repeat to run several operations in one atomic call.

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 integer or null replies, one per subcommand
RESP3	Array of integer or null replies, one per subcommand

Note

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

Examples#

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

Redis CLI

BITFIELD my-key GET u8 0

@upstash/redis

import { Redis } from "@upstash/redis";const redis = Redis.fromEnv();const result = await redis.bitfield("my-key").get("u8", 0).exec();console.log(result);

upstash_redis

from upstash_redis import Redisredis = Redis.from_env()result = redis.bitfield("my-key").get("u8", 0).execute()print(result)

ioredis

import Redis from "ioredis";const redis = new Redis(process.env.REDIS_URL!);const result = await redis.bitfield("my-key", "GET", "u8", "0");console.log(result);

node-redis

import { createClient } from "redis";const client = await createClient({ url: process.env.REDIS_URL })  .on("error", console.error)  .connect();const result = await client.bitField("my-key", [{ operation: "GET", encoding: "u8", offset: 0 }]);console.log(result);

redis-py

import osimport redisclient = redis.from_url(os.environ["REDIS_URL"])result = client.bitfield("my-key").get("u8", 0).execute()print(result)

go-redis

package mainimport (    "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.BitField(context.Background(), "my-key", "GET", "u8", 0).Result()    if err != nil {        panic(err)    }    fmt.Println(result)}

jedis

import java.net.URI;import redis.clients.jedis.Jedis;try (Jedis jedis = new Jedis(new URI(System.getenv("REDIS_URL")))) {  Object result = jedis.bitfield("my-key", "GET", "u8", "0");  System.out.println(result);}

redis-rs

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("BITFIELD");    command.arg("my-key");    let result: redis::Value = command.query(&mut connection)?;    println!("{result:?}");    Ok(())}