{ "PFMERGE": { "summary": "Merges one or more HyperLogLog values into a single key.", "complexity": "O(N) to merge N HyperLogLogs, but with high constant times.", "group": "hyperloglog", "since": "2.8.9", "arity": -2, "function": "pfmergeCommand", "command_flags": [ "WRITE", "DENYOOM" ], "acl_categories": [ "HYPERLOGLOG" ], "key_specs": [ { "flags": [ "RW", "ACCESS", "INSERT" ], "begin_search": { "index": { "pos": 1 } }, "find_keys": { "range": { "lastkey": 0, "step": 1, "limit": 0 } } }, { "flags": [ "RO", "ACCESS" ], "begin_search": { "index": { "pos": 2 } }, "find_keys": { "range": { "lastkey": -1, "step": 1, "limit": 0 } } } ], "arguments": [ { "name": "destkey", "type": "key", "key_spec_index": 0 }, { "name": "sourcekey", "type": "key", "key_spec_index": 1, "optional": true, "multiple": true } ], "reply_schema": { "const": "OK" } } }