Module: Redis::Commands::SortedSets

Included in:
Redis::Commands
Defined in:
lib/redis/commands/sorted_sets.rb

Instance Method Summary collapse

Instance Method Details

#bzpopmax(*args) ⇒ Array<String, String, Float>?

Removes and returns up to count members with the highest scores in the sorted set stored at keys,

or block until one is available.

Examples:

Popping a member from a sorted set

redis.bzpopmax('zset', 1)
#=> ['zset', 'b', 2.0]

Popping a member from multiple sorted sets

redis.bzpopmax('zset1', 'zset2', 1)
#=> ['zset1', 'b', 2.0]

Returns:

  • (Array<String, String, Float>) —

    a touple of key, member and score

  • (nil) —

    when no element could be popped and the timeout expired



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# File 'lib/redis/commands/sorted_sets.rb', line 185

def bzpopmax(*args)
  _bpop(:bzpopmax, args) do |reply|
    reply.is_a?(Array) ? [reply[0], reply[1], Floatify.call(reply[2])] : reply
  end
end

#bzpopmin(*args) ⇒ Array<String, String, Float>?

Removes and returns up to count members with the lowest scores in the sorted set stored at keys,

or block until one is available.

Examples:

Popping a member from a sorted set

redis.bzpopmin('zset', 1)
#=> ['zset', 'a', 1.0]

Popping a member from multiple sorted sets

redis.bzpopmin('zset1', 'zset2', 1)
#=> ['zset1', 'a', 1.0]

Returns:

  • (Array<String, String, Float>) —

    a touple of key, member and score

  • (nil) —

    when no element could be popped and the timeout expired



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# File 'lib/redis/commands/sorted_sets.rb', line 206

def bzpopmin(*args)
  _bpop(:bzpopmin, args) do |reply|
    reply.is_a?(Array) ? [reply[0], reply[1], Floatify.call(reply[2])] : reply
  end
end

#zadd(key, *args, nx: nil, xx: nil, lt: nil, gt: nil, ch: nil, incr: nil) ⇒ Boolean, ...

Add one or more members to a sorted set, or update the score for members that already exist.

Examples:

Add a single ‘[score, member]` pair to a sorted set

redis.zadd("zset", 32.0, "member")

Add an array of ‘[score, member]` pairs to a sorted set

redis.zadd("zset", [[32.0, "a"], [64.0, "b"]])

Parameters:

  • key (String)
  • args ([Float, String], Array<[Float, String]>) —

    • a single ‘[score, member]` pair

    • an array of ‘[score, member]` pairs

  • options (Hash) —

    • ‘:xx => true`: Only update elements that already exist (never

    add elements)

    • ‘:nx => true`: Don’t update already existing elements (always

    add new elements)

    • ‘:lt => true`: Only update existing elements if the new score

    is less than the current score

    • ‘:gt => true`: Only update existing elements if the new score

    is greater than the current score

    • ‘:ch => true`: Modify the return value from the number of new

    elements added, to the total number of elements changed (CH is an abbreviation of changed); changed elements are new elements added and elements already existing for which the score was updated

    • ‘:incr => true`: When this option is specified ZADD acts like

    ZINCRBY; only one score-element pair can be specified in this mode

Returns:

  • (Boolean, Integer, Float) —

    • ‘Boolean` when a single pair is specified, holding whether or not it was

    added to the sorted set.

    • ‘Integer` when an array of pairs is specified, holding the number of

    pairs that were added to the sorted set.

    • ‘Float` when option :incr is specified, holding the score of the member

    after incrementing it.



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# File 'lib/redis/commands/sorted_sets.rb', line 53

def zadd(key, *args, nx: nil, xx: nil, lt: nil, gt: nil, ch: nil, incr: nil)
  command = [:zadd, key]
  command << "NX" if nx
  command << "XX" if xx
  command << "LT" if lt
  command << "GT" if gt
  command << "CH" if ch
  command << "INCR" if incr

  if args.size == 1 && args[0].is_a?(Array)
    members_to_add = args[0]
    return 0 if members_to_add.empty?

    # Variadic: return float if INCR, integer if !INCR
    send_command(command + members_to_add, &(incr ? Floatify : nil))
  elsif args.size == 2
    # Single pair: return float if INCR, boolean if !INCR
    send_command(command + args, &(incr ? Floatify : Boolify))
  else
    raise ArgumentError, "wrong number of arguments"
  end
end

#zcard(key) ⇒ Integer

Get the number of members in a sorted set.

Examples:

redis.zcard("zset")
  # => 4

Parameters:

  • key (String)

Returns:

  • (Integer) 


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# File 'lib/redis/commands/sorted_sets.rb', line 14

def zcard(key)
  send_command([:zcard, key])
end

#zcount(key, min, max) ⇒ Integer

Count the members in a sorted set with scores within the given values.

Examples:

Count members with score ‘>= 5` and `< 100`

redis.zcount("zset", "5", "(100")
  # => 2

Count members with scores ‘> 5`

redis.zcount("zset", "(5", "+inf")
  # => 2

Parameters:

  • key (String)
  • min (String) —

    • inclusive minimum score is specified verbatim

    • exclusive minimum score is specified by prefixing ‘(`

  • max (String) —

    • inclusive maximum score is specified verbatim

    • exclusive maximum score is specified by prefixing ‘(`

Returns:

  • (Integer) —

    number of members in within the specified range



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# File 'lib/redis/commands/sorted_sets.rb', line 612

def zcount(key, min, max)
  send_command([:zcount, key, min, max])
end

#zdiff(*keys, with_scores: false) ⇒ Array<String>, Array<[String, Float]>

Return the difference between the first and all successive input sorted sets

Examples:

redis.zadd("zsetA", [[1.0, "v1"], [2.0, "v2"]])
redis.zadd("zsetB", [[3.0, "v2"], [2.0, "v3"]])
redis.zdiff("zsetA", "zsetB")
  => ["v1"]

With scores

redis.zadd("zsetA", [[1.0, "v1"], [2.0, "v2"]])
redis.zadd("zsetB", [[3.0, "v2"], [2.0, "v3"]])
redis.zdiff("zsetA", "zsetB", :with_scores => true)
  => [["v1", 1.0]]

Parameters:

  • keys (String, Array<String>) —

    one or more keys to compute the difference

  • options (Hash) —

    • ‘:with_scores => true`: include scores in output

Returns:

  • (Array<String>, Array<[String, Float]>) —

    • when ‘:with_scores` is not specified, an array of members

    • when ‘:with_scores` is specified, an array with `[member, score]` pairs



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# File 'lib/redis/commands/sorted_sets.rb', line 721

def zdiff(*keys, with_scores: false)
  _zsets_operation(:zdiff, *keys, with_scores: with_scores)
end

#zdiffstore(*args) ⇒ Integer

Compute the difference between the first and all successive input sorted sets and store the resulting sorted set in a new key

Examples:

redis.zadd("zsetA", [[1.0, "v1"], [2.0, "v2"]])
redis.zadd("zsetB", [[3.0, "v2"], [2.0, "v3"]])
redis.zdiffstore("zsetA", "zsetB")
  # => 1

Parameters:

  • destination (String) —

    destination key

  • keys (Array<String>) —

    source keys

Returns:

  • (Integer) —

    number of elements in the resulting sorted set



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# File 'lib/redis/commands/sorted_sets.rb', line 737

def zdiffstore(*args)
  _zsets_operation_store(:zdiffstore, *args)
end

#zincrby(key, increment, member) ⇒ Float

Increment the score of a member in a sorted set.

Examples:

redis.zincrby("zset", 32.0, "a")
  # => 64.0

Parameters:

  • key (String)
  • increment (Float)
  • member (String)

Returns:

  • (Float) —

    score of the member after incrementing it



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# File 'lib/redis/commands/sorted_sets.rb', line 86

def zincrby(key, increment, member)
  send_command([:zincrby, key, increment, member], &Floatify)
end

#zinter(*args) ⇒ Array<String>, Array<[String, Float]>

Return the intersection of multiple sorted sets

Examples:

Retrieve the intersection of ‘2*zsetA` and `1*zsetB`

redis.zinter("zsetA", "zsetB", :weights => [2.0, 1.0])
  # => ["v1", "v2"]

Retrieve the intersection of ‘2*zsetA` and `1*zsetB`, and their scores

redis.zinter("zsetA", "zsetB", :weights => [2.0, 1.0], :with_scores => true)
  # => [["v1", 3.0], ["v2", 6.0]]

Parameters:

  • keys (String, Array<String>) —

    one or more keys to intersect

  • options (Hash) —

    • ‘:weights => [Float, Float, …]`: weights to associate with source

    sorted sets

    • ‘:aggregate => String`: aggregate function to use (sum, min, max, …)

    • ‘:with_scores => true`: include scores in output

Returns:

  • (Array<String>, Array<[String, Float]>) —

    • when ‘:with_scores` is not specified, an array of members

    • when ‘:with_scores` is specified, an array with `[member, score]` pairs



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# File 'lib/redis/commands/sorted_sets.rb', line 635

def zinter(*args)
  _zsets_operation(:zinter, *args)
end

#zinterstore(*args) ⇒ Integer

Intersect multiple sorted sets and store the resulting sorted set in a new key.

Examples:

Compute the intersection of ‘2*zsetA` with `1*zsetB`, summing their scores

redis.zinterstore("zsetC", ["zsetA", "zsetB"], :weights => [2.0, 1.0], :aggregate => "sum")
  # => 4

Parameters:

  • destination (String) —

    destination key

  • keys (Array<String>) —

    source keys

  • options (Hash) —

    • ‘:weights => [Array<Float>]`: weights to associate with source

    sorted sets

    • ‘:aggregate => String`: aggregate function to use (sum, min, max)

Returns:

  • (Integer) —

    number of elements in the resulting sorted set



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# File 'lib/redis/commands/sorted_sets.rb', line 654

def zinterstore(*args)
  _zsets_operation_store(:zinterstore, *args)
end

#zlexcount(key, min, max) ⇒ Integer

Count the members, with the same score in a sorted set, within the given lexicographical range.

Examples:

Count members matching a

redis.zlexcount("zset", "[a", "[a\xff")
  # => 1

Count members matching a-z

redis.zlexcount("zset", "[a", "[z\xff")
  # => 26

Parameters:

  • key (String)
  • min (String) —

    • inclusive minimum is specified by prefixing ‘(`

    • exclusive minimum is specified by prefixing ‘[`

  • max (String) —

    • inclusive maximum is specified by prefixing ‘(`

    • exclusive maximum is specified by prefixing ‘[`

Returns:

  • (Integer) —

    number of members within the specified lexicographical range



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# File 'lib/redis/commands/sorted_sets.rb', line 443

def zlexcount(key, min, max)
  send_command([:zlexcount, key, min, max])
end

#zmscore(key, *members) ⇒ Array<Float>

Get the scores associated with the given members in a sorted set.

Examples:

Get the scores for members “a” and “b”

redis.zmscore("zset", "a", "b")
  # => [32.0, 48.0]

Parameters:

  • key (String)
  • members (String, Array<String>)

Returns:

  • (Array<Float>) —

    scores of the members



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# File 'lib/redis/commands/sorted_sets.rb', line 234

def zmscore(key, *members)
  send_command([:zmscore, key, *members]) do |reply|
    reply.map(&Floatify)
  end
end

#zpopmax(key, count = nil) ⇒ Array<String, Float>+

Removes and returns up to count members with the highest scores in the sorted set stored at key.

Examples:

Popping a member

redis.zpopmax('zset')
#=> ['b', 2.0]

With count option

redis.zpopmax('zset', 2)
#=> [['b', 2.0], ['a', 1.0]]

Returns:

  • (Array<String, Float>) —

    element and score pair if count is not specified

  • (Array<Array<String, Float>>) —

    list of popped elements and scores



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# File 'lib/redis/commands/sorted_sets.rb', line 138

def zpopmax(key, count = nil)
  command = [:zpopmax, key]
  command << Integer(count) if count
  send_command(command) do |members|
    members = FloatifyPairs.call(members)
    count.to_i > 1 ? members : members.first
  end
end

#zpopmin(key, count = nil) ⇒ Array<String, Float>+

Removes and returns up to count members with the lowest scores in the sorted set stored at key.

Examples:

Popping a member

redis.zpopmin('zset')
#=> ['a', 1.0]

With count option

redis.zpopmin('zset', 2)
#=> [['a', 1.0], ['b', 2.0]]

Returns:

  • (Array<String, Float>) —

    element and score pair if count is not specified

  • (Array<Array<String, Float>>) —

    list of popped elements and scores



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# File 'lib/redis/commands/sorted_sets.rb', line 161

def zpopmin(key, count = nil)
  command = [:zpopmin, key]
  command << Integer(count) if count
  send_command(command) do |members|
    members = FloatifyPairs.call(members)
    count.to_i > 1 ? members : members.first
  end
end

#zrandmember(key, count = nil, withscores: false, with_scores: withscores) ⇒ nil, ...

Get one or more random members from a sorted set.

Examples:

Get one random member

redis.zrandmember("zset")
  # => "a"

Get multiple random members

redis.zrandmember("zset", 2)
  # => ["a", "b"]

Get multiple random members with scores

redis.zrandmember("zset", 2, with_scores: true)
  # => [["a", 2.0], ["b", 3.0]]

Parameters:

  • key (String)
  • count (Integer) (defaults to: nil)
  • options (Hash) —

    • ‘:with_scores => true`: include scores in output

Returns:

  • (nil, String, Array<String>, Array<[String, Float]>) —

    • when ‘key` does not exist or set is empty, `nil`

    • when ‘count` is not specified, a member

    • when ‘count` is specified and `:with_scores` is not specified, an array of members

    • when ‘:with_scores` is specified, an array with `[member, score]` pairs



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# File 'lib/redis/commands/sorted_sets.rb', line 262

def zrandmember(key, count = nil, withscores: false, with_scores: withscores)
  if with_scores && count.nil?
    raise ArgumentError, "count argument must be specified"
  end

  args = [:zrandmember, key]
  args << Integer(count) if count

  if with_scores
    args << "WITHSCORES"
    block = FloatifyPairs
  end

  send_command(args, &block)
end

#zrange(key, start, stop, byscore: false, by_score: byscore, bylex: false, by_lex: bylex, rev: false, limit: nil, withscores: false, with_scores: withscores) ⇒ Array<String>, Array<[String, Float]>

Return a range of members in a sorted set, by index, score or lexicographical ordering.

Examples:

Retrieve all members from a sorted set, by index

redis.zrange("zset", 0, -1)
  # => ["a", "b"]

Retrieve all members and their scores from a sorted set

redis.zrange("zset", 0, -1, :with_scores => true)
  # => [["a", 32.0], ["b", 64.0]]

Parameters:

  • key (String)
  • start (Integer) —

    start index

  • stop (Integer) —

    stop index

  • options (Hash) —

    • ‘:by_score => false`: return members by score

    • ‘:by_lex => false`: return members by lexicographical ordering

    • ‘:rev => false`: reverse the ordering, from highest to lowest

    • ‘:limit => [offset, count]`: skip `offset` members, return a maximum of

    ‘count` members

    • ‘:with_scores => true`: include scores in output

Returns:

  • (Array<String>, Array<[String, Float]>) —

    • when ‘:with_scores` is not specified, an array of members

    • when ‘:with_scores` is specified, an array with `[member, score]` pairs



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# File 'lib/redis/commands/sorted_sets.rb', line 301

def zrange(key, start, stop, byscore: false, by_score: byscore, bylex: false, by_lex: bylex,
           rev: false, limit: nil, withscores: false, with_scores: withscores)

  if by_score && by_lex
    raise ArgumentError, "only one of :by_score or :by_lex can be specified"
  end

  args = [:zrange, key, start, stop]

  if by_score
    args << "BYSCORE"
  elsif by_lex
    args << "BYLEX"
  end

  args << "REV" if rev

  if limit
    args << "LIMIT"
    args.concat(limit.map { |l| Integer(l) })
  end

  if with_scores
    args << "WITHSCORES"
    block = FloatifyPairs
  end

  send_command(args, &block)
end

#zrangebylex(key, min, max, limit: nil) ⇒ Array<String>, Array<[String, Float]>

Return a range of members with the same score in a sorted set, by lexicographical ordering

Examples:

Retrieve members matching a

redis.zrangebylex("zset", "[a", "[a\xff")
  # => ["aaren", "aarika", "abagael", "abby"]

Retrieve the first 2 members matching a

redis.zrangebylex("zset", "[a", "[a\xff", :limit => [0, 2])
  # => ["aaren", "aarika"]

Parameters:

  • key (String)
  • min (String) —

    • inclusive minimum is specified by prefixing ‘(`

    • exclusive minimum is specified by prefixing ‘[`

  • max (String) —

    • inclusive maximum is specified by prefixing ‘(`

    • exclusive maximum is specified by prefixing ‘[`

  • options (Hash) —

    • ‘:limit => [offset, count]`: skip `offset` members, return a maximum of

    ‘count` members

Returns:

  • (Array<String>, Array<[String, Float]>) 


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# File 'lib/redis/commands/sorted_sets.rb', line 468

def zrangebylex(key, min, max, limit: nil)
  args = [:zrangebylex, key, min, max]

  if limit
    args << "LIMIT"
    args.concat(limit.map { |l| Integer(l) })
  end

  send_command(args)
end

#zrangebyscore(key, min, max, withscores: false, with_scores: withscores, limit: nil) ⇒ Array<String>, Array<[String, Float]>

Return a range of members in a sorted set, by score.

Examples:

Retrieve members with score ‘>= 5` and `< 100`

redis.zrangebyscore("zset", "5", "(100")
  # => ["a", "b"]

Retrieve the first 2 members with score ‘>= 0`

redis.zrangebyscore("zset", "0", "+inf", :limit => [0, 2])
  # => ["a", "b"]

Retrieve members and their scores with scores ‘> 5`

redis.zrangebyscore("zset", "(5", "+inf", :with_scores => true)
  # => [["a", 32.0], ["b", 64.0]]

Parameters:

  • key (String)
  • min (String) —

    • inclusive minimum score is specified verbatim

    • exclusive minimum score is specified by prefixing ‘(`

  • max (String) —

    • inclusive maximum score is specified verbatim

    • exclusive maximum score is specified by prefixing ‘(`

  • options (Hash) —

    • ‘:with_scores => true`: include scores in output

    • ‘:limit => [offset, count]`: skip `offset` members, return a maximum of

    ‘count` members

Returns:

  • (Array<String>, Array<[String, Float]>) —

    • when ‘:with_scores` is not specified, an array of members

    • when ‘:with_scores` is specified, an array with `[member, score]` pairs



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# File 'lib/redis/commands/sorted_sets.rb', line 528

def zrangebyscore(key, min, max, withscores: false, with_scores: withscores, limit: nil)
  args = [:zrangebyscore, key, min, max]

  if with_scores
    args << "WITHSCORES"
    block = FloatifyPairs
  end

  if limit
    args << "LIMIT"
    args.concat(limit.map { |l| Integer(l) })
  end

  send_command(args, &block)
end

#zrangestore(dest_key, src_key, start, stop, byscore: false, by_score: byscore, bylex: false, by_lex: bylex, rev: false, limit: nil) ⇒ Integer

Select a range of members in a sorted set, by index, score or lexicographical ordering and store the resulting sorted set in a new key.

Examples:

redis.zadd("foo", [[1.0, "s1"], [2.0, "s2"], [3.0, "s3"]])
redis.zrangestore("bar", "foo", 0, 1)
  # => 2
redis.zrange("bar", 0, -1)
  # => ["s1", "s2"]

Returns:

  • (Integer) —

    the number of elements in the resulting sorted set

See Also:



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# File 'lib/redis/commands/sorted_sets.rb', line 343

def zrangestore(dest_key, src_key, start, stop, byscore: false, by_score: byscore,
                bylex: false, by_lex: bylex, rev: false, limit: nil)
  if by_score && by_lex
    raise ArgumentError, "only one of :by_score or :by_lex can be specified"
  end

  args = [:zrangestore, dest_key, src_key, start, stop]

  if by_score
    args << "BYSCORE"
  elsif by_lex
    args << "BYLEX"
  end

  args << "REV" if rev

  if limit
    args << "LIMIT"
    args.concat(limit.map { |l| Integer(l) })
  end

  send_command(args)
end

#zrank(key, member) ⇒ Integer

Determine the index of a member in a sorted set.

Parameters:

  • key (String)
  • member (String)

Returns:

  • (Integer) 


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# File 'lib/redis/commands/sorted_sets.rb', line 394

def zrank(key, member)
  send_command([:zrank, key, member])
end

#zrem(key, member) ⇒ Boolean, Integer

Remove one or more members from a sorted set.

Examples:

Remove a single member from a sorted set

redis.zrem("zset", "a")

Remove an array of members from a sorted set

redis.zrem("zset", ["a", "b"])

Parameters:

  • key (String)
  • member (String, Array<String>) —

    • a single member

    • an array of members

Returns:

  • (Boolean, Integer) —

    • ‘Boolean` when a single member is specified, holding whether or not it

    was removed from the sorted set

    • ‘Integer` when an array of pairs is specified, holding the number of

    members that were removed to the sorted set



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# File 'lib/redis/commands/sorted_sets.rb', line 107

def zrem(key, member)
  if member.is_a?(Array)
    members_to_remove = member
    return 0 if members_to_remove.empty?
  end

  send_command([:zrem, key, member]) do |reply|
    if member.is_a? Array
      # Variadic: return integer
      reply
    else
      # Single argument: return boolean
      Boolify.call(reply)
    end
  end
end

#zremrangebyrank(key, start, stop) ⇒ Integer

Remove all members in a sorted set within the given indexes.

Examples:

Remove first 5 members

redis.zremrangebyrank("zset", 0, 4)
  # => 5

Remove last 5 members

redis.zremrangebyrank("zset", -5, -1)
  # => 5

Parameters:

  • key (String)
  • start (Integer) —

    start index

  • stop (Integer) —

    stop index

Returns:

  • (Integer) —

    number of members that were removed



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# File 'lib/redis/commands/sorted_sets.rb', line 421

def zremrangebyrank(key, start, stop)
  send_command([:zremrangebyrank, key, start, stop])
end

#zremrangebyscore(key, min, max) ⇒ Integer

Remove all members in a sorted set within the given scores.

Examples:

Remove members with score ‘>= 5` and `< 100`

redis.zremrangebyscore("zset", "5", "(100")
  # => 2

Remove members with scores ‘> 5`

redis.zremrangebyscore("zset", "(5", "+inf")
  # => 2

Parameters:

  • key (String)
  • min (String) —

    • inclusive minimum score is specified verbatim

    • exclusive minimum score is specified by prefixing ‘(`

  • max (String) —

    • inclusive maximum score is specified verbatim

    • exclusive maximum score is specified by prefixing ‘(`

Returns:

  • (Integer) —

    number of members that were removed



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# File 'lib/redis/commands/sorted_sets.rb', line 591

def zremrangebyscore(key, min, max)
  send_command([:zremrangebyscore, key, min, max])
end

#zrevrange(key, start, stop, withscores: false, with_scores: withscores) ⇒ Object

Return a range of members in a sorted set, by index, with scores ordered from high to low.

Examples:

Retrieve all members from a sorted set

redis.zrevrange("zset", 0, -1)
  # => ["b", "a"]

Retrieve all members and their scores from a sorted set

redis.zrevrange("zset", 0, -1, :with_scores => true)
  # => [["b", 64.0], ["a", 32.0]]

See Also:



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# File 'lib/redis/commands/sorted_sets.rb', line 378

def zrevrange(key, start, stop, withscores: false, with_scores: withscores)
  args = [:zrevrange, key, Integer(start), Integer(stop)]

  if with_scores
    args << "WITHSCORES"
    block = FloatifyPairs
  end

  send_command(args, &block)
end

#zrevrangebylex(key, max, min, limit: nil) ⇒ Object

Return a range of members with the same score in a sorted set, by reversed lexicographical ordering. Apart from the reversed ordering, #zrevrangebylex is similar to #zrangebylex.

Examples:

Retrieve members matching a

redis.zrevrangebylex("zset", "[a", "[a\xff")
  # => ["abbygail", "abby", "abagael", "aaren"]

Retrieve the last 2 members matching a

redis.zrevrangebylex("zset", "[a", "[a\xff", :limit => [0, 2])
  # => ["abbygail", "abby"]

See Also:



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# File 'lib/redis/commands/sorted_sets.rb', line 490

def zrevrangebylex(key, max, min, limit: nil)
  args = [:zrevrangebylex, key, max, min]

  if limit
    args << "LIMIT"
    args.concat(limit.map { |l| Integer(l) })
  end

  send_command(args)
end

#zrevrangebyscore(key, max, min, withscores: false, with_scores: withscores, limit: nil) ⇒ Object

Return a range of members in a sorted set, by score, with scores ordered from high to low.

Examples:

Retrieve members with score ‘< 100` and `>= 5`

redis.zrevrangebyscore("zset", "(100", "5")
  # => ["b", "a"]

Retrieve the first 2 members with score ‘<= 0`

redis.zrevrangebyscore("zset", "0", "-inf", :limit => [0, 2])
  # => ["b", "a"]

Retrieve members and their scores with scores ‘> 5`

redis.zrevrangebyscore("zset", "+inf", "(5", :with_scores => true)
  # => [["b", 64.0], ["a", 32.0]]

See Also:



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# File 'lib/redis/commands/sorted_sets.rb', line 558

def zrevrangebyscore(key, max, min, withscores: false, with_scores: withscores, limit: nil)
  args = [:zrevrangebyscore, key, max, min]

  if with_scores
    args << "WITHSCORES"
    block = FloatifyPairs
  end

  if limit
    args << "LIMIT"
    args.concat(limit.map { |l| Integer(l) })
  end

  send_command(args, &block)
end

#zrevrank(key, member) ⇒ Integer

Determine the index of a member in a sorted set, with scores ordered from high to low.

Parameters:

  • key (String)
  • member (String)

Returns:

  • (Integer) 


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# File 'lib/redis/commands/sorted_sets.rb', line 404

def zrevrank(key, member)
  send_command([:zrevrank, key, member])
end

#zscan(key, cursor, **options) ⇒ String, Array<[String, Float]>

Scan a sorted set

Examples:

Retrieve the first batch of key/value pairs in a hash

redis.zscan("zset", 0)

Parameters:

  • cursor (String, Integer) —

    the cursor of the iteration

  • options (Hash) —

    • ‘:match => String`: only return keys matching the pattern

    • ‘:count => Integer`: return count keys at most per iteration

Returns:

  • (String, Array<[String, Float]>) —

    the next cursor and all found members and scores



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# File 'lib/redis/commands/sorted_sets.rb', line 754

def zscan(key, cursor, **options)
  _scan(:zscan, cursor, [key], **options) do |reply|
    [reply[0], FloatifyPairs.call(reply[1])]
  end
end

#zscan_each(key, **options, &block) ⇒ Enumerator

Scan a sorted set

Examples:

Retrieve all of the members/scores in a sorted set

redis.zscan_each("zset").to_a
# => [["key70", "70"], ["key80", "80"]]

Parameters:

  • options (Hash) —

    • ‘:match => String`: only return keys matching the pattern

    • ‘:count => Integer`: return count keys at most per iteration

Returns:

  • (Enumerator) —

    an enumerator for all found scores and members



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# File 'lib/redis/commands/sorted_sets.rb', line 771

def zscan_each(key, **options, &block)
  return to_enum(:zscan_each, key, **options) unless block_given?

  cursor = 0
  loop do
    cursor, values = zscan(key, cursor, **options)
    values.each(&block)
    break if cursor == "0"
  end
end

#zscore(key, member) ⇒ Float

Get the score associated with the given member in a sorted set.

Examples:

Get the score for member “a”

redis.zscore("zset", "a")
  # => 32.0

Parameters:

  • key (String)
  • member (String)

Returns:

  • (Float) —

    score of the member



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# File 'lib/redis/commands/sorted_sets.rb', line 221

def zscore(key, member)
  send_command([:zscore, key, member], &Floatify)
end

#zunion(*args) ⇒ Array<String>, Array<[String, Float]>

Return the union of multiple sorted sets

Examples:

Retrieve the union of ‘2*zsetA` and `1*zsetB`

redis.zunion("zsetA", "zsetB", :weights => [2.0, 1.0])
  # => ["v1", "v2"]

Retrieve the union of ‘2*zsetA` and `1*zsetB`, and their scores

redis.zunion("zsetA", "zsetB", :weights => [2.0, 1.0], :with_scores => true)
  # => [["v1", 3.0], ["v2", 6.0]]

Parameters:

  • keys (String, Array<String>) —

    one or more keys to union

  • options (Hash) —

    • ‘:weights => [Array<Float>]`: weights to associate with source

    sorted sets

    • ‘:aggregate => String`: aggregate function to use (sum, min, max)

    • ‘:with_scores => true`: include scores in output

Returns:

  • (Array<String>, Array<[String, Float]>) —

    • when ‘:with_scores` is not specified, an array of members

    • when ‘:with_scores` is specified, an array with `[member, score]` pairs



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# File 'lib/redis/commands/sorted_sets.rb', line 678

def zunion(*args)
  _zsets_operation(:zunion, *args)
end

#zunionstore(*args) ⇒ Integer

Add multiple sorted sets and store the resulting sorted set in a new key.

Examples:

Compute the union of ‘2*zsetA` with `1*zsetB`, summing their scores

redis.zunionstore("zsetC", ["zsetA", "zsetB"], :weights => [2.0, 1.0], :aggregate => "sum")
  # => 8

Parameters:

  • destination (String) —

    destination key

  • keys (Array<String>) —

    source keys

  • options (Hash) —

    • ‘:weights => [Float, Float, …]`: weights to associate with source

    sorted sets

    • ‘:aggregate => String`: aggregate function to use (sum, min, max, …)

Returns:

  • (Integer) —

    number of elements in the resulting sorted set



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# File 'lib/redis/commands/sorted_sets.rb', line 696

def zunionstore(*args)
  _zsets_operation_store(:zunionstore, *args)
end