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Client.hsetnx(key, field, value)
Sets the specified field in the hash stored at key to value, only if field does not yet exist. If key does not exist, a new key holding a hash is created. If field already exists, this operation has no effect.
Parameters
| Parameter | Type | Description |
|---|---|---|
key | string | key holding the hash to set the field of. |
field | string | field to set in the hash. |
value | string | value to set the field to. |
Returns
| Type | Resolves with | Rejected when |
|---|---|---|
Promise<boolean> | On success, the promise resolves with 1 if field is a new field in the hash and value was set, and with 0 if field already exists in the hash and no operation was performed. |
Example
JavaScript
import redis from 'k6/x/redis';
// Instantiate a new redis client
const redisClient = new redis.Client('redis://localhost:6379');
export default async function () {
await redisClient.hsetnx('myhash', 'myfield', 'myvalue');
await redisClient.hsetnx('myhash', 'myotherfield', 'myothervalue');
const set = await redisClient.hsetnx('myhash', 'myfield', 'mynewvalue');
if (set === true) {
throw new Error('hsetnx should have failed on existing field');
}
}Was this page helpful?
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