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# ZDIFFSTORE

> Writes the difference between sets to a new key.

## Arguments 

<ParamField body="destination" type="string" required>
  The key to write the difference to.
</ParamField>

<ParamField body="keys" type="integer" required>
  How many keys to compare.
</ParamField>

<ParamField body="keys" type="...string[]" required>
  The keys to compare.
</ParamField>

## Response

<ResponseField  required>
    The number of elements in the resulting set.
</ResponseField>

<RequestExample>
```ts Example
const values = await redis.zdiffstore("destination", 2, "key1", "key2");
```
</RequestExample>