BZMPOP

BZMPOP is the blocking form of ZMPOP. It checks the keys in order and pops up to count members (default 1) from the first non-empty sorted set: the lowest scores with MIN, the highest with MAX. If every sorted set is empty or missing, the connection waits until one of the keys gets members or timeout passes, then pops from that key.

timeout is in seconds, can have a fractional part, and 0 waits forever. Inside MULTI / EXEC and inside scripts, BZMPOP never waits and replies at once as if the timeout had expired.

Options

Option	Effect
timeout	Seconds to wait; 0 waits forever.
numkeys	How many keys follow. Must be greater than 0.
MIN / MAX	Pop the lowest or the highest scores.
COUNT count	Pop up to count members. Must be greater than 0.

The arguments after timeout are checked before timeout itself.

Return value

Case	RESP2	RESP3
Popped	Two-element array: the key, then an array of [member, score] pairs (score as a bulk string)	Same shape, with each score a double
Timeout expired	Nil array	Null

Errors:

• ERR numkeys should be greater than 0, ERR count should be greater than 0, or ERR syntax error, as for ZMPOP.
• ERR timeout is not a float or out of range, ERR timeout is negative, or ERR timeout is out of range for a bad timeout.
• WRONGTYPE if a key reached before the first non-empty sorted set holds a value that is not a sorted set.

Examples

127.0.0.1:6379> ZADD board 100 "alice" 90 "bob" 80 "carol"
(integer) 3
127.0.0.1:6379> BZMPOP 1 1 board MAX COUNT 2
1) "board"
2) 1) 1) "alice"
      2) "100"
   2) 1) "bob"
      2) "90"
127.0.0.1:6379> BZMPOP 0.3 1 empty MIN
(nil)
(0.30s)

Compatibility

Same as Redis 7.4 and Valkey 8.

See also

ZMPOP, BZPOPMIN, BZPOPMAX, BLMPOP