XDEL command is used with Redis streams to delete one or more messages from a stream by their ID. Common use cases include:
In Java, you can use the Lettuce library to interact with Redis, including using the
xdel command. Here are some examples of how to do this:
Example 1: Deleting a single message
In this example, we first add a message to the stream "mystream" and then immediately delete it using its ID.
Example 2: Deleting multiple messages
This example shows how to delete multiple messages at once. We add two messages to the stream and then delete them both using their IDs.
XDEL if you need to remove specific messages. If you want to remove all messages, consider using
XTRIM with a limit of 0, as it can be more efficient.
Be careful when deleting messages if other clients are reading from the stream. If a client is blocked waiting for a message you delete, it may never unblock.
Q: Can I use the
XDEL command to delete all messages in a stream?
XDEL requires specific IDs and cannot delete all messages. If you want to delete all messages, consider using
XTRIM with a limit of 0.
Q: What happens if I try to
XDEL a message that has already been deleted?
A: Redis will simply return 0 to indicate no messages were deleted. It will not raise an error if you try to delete a message that does not exist.