Delete All Keys in Redis using Java (Detailed Guide w/ Code Examples)

Use Case(s)

Often during development or testing, you might need to clear out your Redis data store. One way to do this is by deleting all keys from it. This might also be necessary when you want to reset the entire cache.

Code Example(s)

Here's how you can delete all keys from a Redis data store using Java with Jedis library:

import redis.clients.jedis.Jedis;

public class Main {
  public static void main(String[] args) {
    Jedis jedis = new Jedis("localhost");
    jedis.flushDB();
  }
}

In this example, jedis.flushDB() is used to delete all keys from the current database.

Best Practices

1. Be cautious while using flushDB() method as it will remove all the keys of the selected DB and there's no undo.
2. You should not use this operation frequently in a production environment as it can affect performance.

Common Mistakes

One common mistake is to use flushAll() instead of flushDB(). The flushAll() command clears all databases in the Redis instance, which might lead to data loss if not intended.

FAQs

Q: Can I delete keys matching a certain pattern? A: Yes, you can use the keys() method combined with a loop to delete keys matching a certain pattern.

Q: What if I want to delete all keys across all databases? A: If you really need to do this, you can use the flushAll() method. But be cautious as it's a dangerous operation especially in production environments.