XADDAppend an entry to a stream, with optional trim.
| Syntax | XADD key [NOMKSTREAM] [MAXLEN|MINID [=|~] threshold [LIMIT count]] id|* field value [field value ...] |
| Group | stream |
| Arity | -5 |
| Since | 1.0.0 |
| Flags | write |
| Complexity | O(log N) to insert; O(N*F) whenever a MAXLEN / MINID clause actually evicts, because the trim triggers a full weight recompute |
| Redis compatibility | differs: answers as valkey 9.1 does, an approximate '~' trim included: it removes only whole nodes of the stream's layout (at most 100 entries or 4 KB of fields each, the fixed stream-node-max-entries / stream-node-max-bytes defaults), up to LIMIT entries (10000 unless given, 0 for no limit); Redis 8.10's KEEPREF / DELREF / ACKED and IDMP / IDMPAUTO options are not parsed |