(PECL memcached >= 2.0.0)
Memcached::deleteMultiByKey — Delete multiple items from a specific server
Memcached::deleteMultiByKey() is functionally equivalent to
Memcached::deleteMulti(), except that the free-form
server_key can be used to map the
keys to a specific server.
server_key本键名用于识别储存和读取值的服务器。没有将实际的键名散列到具体的项目，而是在决定与哪一个 memcached 服务器通信时将其散列为服务器键名。这使得关联的项目在单一的服务上被组合起来以提高多重操作的效率。
keysThe keys to be deleted.
timeThe amount of time the server will wait to delete the items.
注意: As of memcached 1.3.0 (released 2009) this feature is no longer supported. Passing a non-zero
timewill cause the deletion to fail. Memcached::getResultCode() will returnMEMCACHED_INVALID_ARGUMENTS.
Returns an array indexed by keys. Each element
is true if the corresponding key was deleted, or one of the
Memcached::RES_* constants if the corresponding deletion
failed.
The Memcached::getResultCode() will return
the result code for the last executed delete operation, that is, the delete
operation for the last element of keys.