Time Complexity: O(1)
ACL categories: @read, @stream, @fast
Returns the number of entries inside a stream. If the specified key does not exist the command returns zero, as if the stream was empty. Note that a stream can be empty and hence XLEN is not a good option to check if a stream exists.
Streams are not auto-deleted once they have no entries inside (for instance after an XDEL call), because the stream may have consumer groups associated with it.
Integer reply: the number of entries of the stream at key.
dragonfly> XADD mystream * name John
dragonfly> XADD mystream * name Bob
dragonfly> XADD mystream * name Alice
dragonfly> XLEN mystream