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

# SDIFF

> Get the difference between sets

Returns the members of the set resulting from the difference between the first set and all the successive sets. Keys that do not exist are considered to be empty sets.

## Usage

```typescript theme={null}
await redis.sdiff(key, ...keys);
```

## Parameters

<ParamField body="key" type="string" required>
  The first set key (the set to subtract from)
</ParamField>

<ParamField body="keys" type="string[]">
  Additional set keys to subtract from the first set
</ParamField>

## Response

<ResponseField name="result" type="TData[]">
  An array containing the members of the resulting set (difference of the sets)
</ResponseField>

## Examples

### Difference between two sets

```typescript theme={null}
await redis.sadd("set1", "a", "b", "c", "d");
await redis.sadd("set2", "c", "d", "e", "f");

const result = await redis.sdiff("set1", "set2");
console.log(result); // ["a", "b"]
```

### Difference with multiple sets

```typescript theme={null}
await redis.sadd("all:items", "item1", "item2", "item3", "item4", "item5");
await redis.sadd("sold:items", "item2", "item4");
await redis.sadd("reserved:items", "item5");

const available = await redis.sdiff(
  "all:items",
  "sold:items",
  "reserved:items"
);
console.log(available); // ["item1", "item3"]
```

### Find unique skills

```typescript theme={null}
await redis.sadd("team:skills", "javascript", "python", "go", "rust");
await redis.sadd("required:skills", "javascript", "python");

const bonusSkills = await redis.sdiff("team:skills", "required:skills");
console.log(bonusSkills); // ["go", "rust"]
```

### Difference with non-existing set

```typescript theme={null}
await redis.sadd("set1", "a", "b", "c");

const result = await redis.sdiff("set1", "nonexistent");
console.log(result); // ["a", "b", "c"]
```

### Order matters

```typescript theme={null}
await redis.sadd("set1", "a", "b", "c");
await redis.sadd("set2", "b", "c", "d");

console.log(await redis.sdiff("set1", "set2")); // ["a"]
console.log(await redis.sdiff("set2", "set1")); // ["d"]
```