ledisdb/doc/commands.md

Summary

ledisdb use redis protocol called RESP(REdis Serialization Protocol), here.

ledisdb all commands return RESP format and it will use int64 instead of RESP integer, string instead of RESP simple string, bulk string instead of RESP bulk string, and array instead of RESP arrays below.

Table of Contents

• Summary
• KV
  • DECR key
  • DECRBY key decrement
  • DEL key [key ...]
  • EXISTS key
  • GET key
  • GETSET key value
  • INCR key
  • INCRBY key increment
  • MGET key [key ...]
  • MSET key value [key value ...]
  • SET key value
  • SETNX key value
  • EXPIRE key seconds
  • EXPIREAT key timestamp
  • TTL key
  • PERSIST key
  • SCAN key [MATCH match] [COUNT count]
• Hash
  • HDEL key field [field ...]
  • HEXISTS key field
  • HGET key field
  • HGETALL key
  • HINCRBY key field increment
  • HKEYS key
  • HLEN key
  • HMGET key field [field ...]
  • HMSET key field value [field value ...]
  • HSET key field value
  • HVALS key
  • HCLEAR key
  • HMCLEAR key [key...]
  • HEXPIRE key seconds
  • HEXPIREAT key timestamp
  • HTTL key
  • HPERSIST key
  • HSCAN key [MATCH match] [COUNT count]
• List
  • LINDEX key index
  • LLEN key
  • LPOP key
  • LRANGE key start stop
  • LPUSH key value [value ...]
  • RPOP key
  • RPUSH key value [value ...]
  • LCLEAR key
  • LMCLEAR key [key...]
  • LEXPIRE key seconds
  • LEXPIREAT key timestamp
  • LTTL key
  • LPERSIST key
  • LSCAN key [MATCH match] [COUNT count]
• Set
  • SADD key member [member ...]
  • SCARD key
  • SDIFF key [key ...]
  • SDIFFSTORE destination key [key ...]
  • SINTER key [key ...]
  • SINTERSTORE destination key [key ...]
  • SISMEMBER key member
  • SMEMBERS key
  • SREM key member [member]
  • SUNION key [key ...]
  • SUNIONSTORE destination key [key ...]
  • SCLEAR key
  • SMCLEAR key [key...]
  • SEXPIRE key seconds
  • SEXPIREAT key timestamp
  • STTL key
  • SPERSIST key
  • SSCAN key [MATCH match] [COUNT count]
• ZSet
  • ZADD key score member [score member ...]
  • ZCARD key
  • ZCOUNT key min max
  • ZINCRBY key increment member
  • ZRANGE key start stop [WITHSCORES]
  • ZRANGEBYSCORE key min max [WITHSCORES] [LIMIT offset count]
  • ZRANK key member
  • ZREM key member [member ...]
  • ZREMRANGEBYRANK key start stop
  • ZREMRANGEBYSCORE key min max
  • ZREVRANGE key start stop [WITHSCORES]
  • ZREVRANGEBYSCORE key max min [WITHSCORES] [LIMIT offset count]
  • ZREVRANK key member
  • ZSCORE key member
  • ZCLEAR key
  • ZMCLEAR key [key ...]
  • ZEXPIRE key seconds
  • ZEXPIREAT key timestamp
  • ZTTL key
  • ZPERSIST key
  • ZUNIONSTORE destination numkeys key [key ...] [WEIGHTS weight [weight ...]] [AGGREGATE SUM|MIN|MAX]
  • ZINTERSTORE destination numkeys key [key ...] [WEIGHTS weight [weight ...]] [AGGREGATE SUM|MIN|MAX]
  • ZSCAN key [MATCH match] [COUNT count]
• Bitmap
  • BGET key
  • BGETBIT key offset
  • BSETBIT key offset value
  • BMSETBIT key offset value[offset value ...]
  • BOPT operation destkey key [key ...]
  • BCOUNT key [start, end]
  • BEXPIRE key seconds
  • BEXPIREAT key timestamp
  • BTTL key
  • BPERSIST key
  • BSCAN key [MATCH match] [COUNT count]
• Replication
  • SLAVEOF host port
  • FULLSYNC
  • SYNC index offset
• Server
  • PING
  • ECHO message
  • SELECT index
• Transaction
  • BEGIN
  • ROLLBACK
  • COMMIT

KV

DECR key

Decrements the number stored at key by one. If the key does not exist, it is set to 0 before decrementing. An error returns if the value for the key is a wrong type that can not be represented as a signed 64 bit integer.

Return value

int64: the value of key after the decrement

Examples

ledis> DECR mykey
(integer) -1
ledis> DECR mykey
(integer) -2
ledis> SET mykey "234293482390480948029348230948"
OK
ledis> DECR mykey
ERR strconv.ParseInt: parsing "234293482390480948029348230948“: invalid syntax

DECRBY key decrement

Decrements the number stored at key by decrement. like DECR.

Return value

int64: the value of key after the decrement

Examples

ledis> SET mykey “10“
OK
ledis> DECRBY mykey “5“
(integer) 5

DEL key [key ...]

Removes the specified keys.

Return value

int64: The number of input keys

Examples

ledis> SET key1 "hello"
OK
ledis> SET key2 "world"
OK
ledis> DEL key1 key2
(integer) 2

EXISTS key

Returns if key exists

Return value

int64, specifically:

• 1 if the key exists.
• 0 if the key does not exists.

Examples

ledis> SET key1 "hello"
OK
ledis> EXISTS key1
(integer) 1
ledis> EXISTS key2
(integer) 0

GET key

Get the value of key. If the key does not exists, it returns nil value.

Return value

bulk: the value of key, or nil when key does not exist.

Examples

ledis> GET nonexisting
(nil)
ledis> SET mykey "hello"
OK
ledis> GET mykey
"hello"

GETSET key value

Atomically sets key to value and returns the old value stored at key.

Return value

bulk: the old value stored at key, or nil when key did not exists.

Examples

ledis> SET mykey "hello"
OK
ledis> GETSET mykey "world"
"hello"
ledis> GET mykey
"world"

INCR key

Increments the number stored at key by one. If the key does not exists, it is SET to 0 before incrementing.

Return value

int64: the value of key after the increment

Examples

ledis> SET mykey "10"
OK
ledis> INCR mykey
(integer) 11
ledis> GET mykey
"11"

INCRBY key increment

Increments the number stored at key by increment. If the key does not exists, it is SET to 0 before incrementing.

Return value

int64: the value of key after the increment

Examples

ledis> SET mykey "10"
OK
ledis> INCRBY mykey 5
(integer) 15

MGET key [key ...]

Returns the values of all specified keys. If the key does not exists, a nil will return.

Return value

array: list of values at the specified keys

Examples

ledis> SET key1 "hello"
OK
ledis> SET key2 "world"
OK
ledis> MGET key1 key2 nonexisting
1) "hello"
2) "world"
3) (nil)

MSET key value [key value ...]

Sets the given keys to their respective values.

Return value

string: always OK

Examples

ledis> MSET key1 "hello" key2 "world"
OK
ledis> GET key1
"hello"
ledis> GET key2
"world"

SET key value

Set key to the value.

Return value

string: OK

Examples

ledis> SET mykey "hello"
OK
ledis> GET mykey
"hello"

SETNX key value

Set key to the value if key does not exist. If key already holds a value, no operation is performed.

Return value

int64:

• 1 if the key was SET
• 0 if the key was not SET

Examples

ledis> SETNX mykey "hello"
(integer) 1
ledis> SETNX mykey "world"
(integer) 0
ledis> GET mykey
"hello"

EXPIRE key seconds

Set a timeout on key. After the timeout has expired, the key will be deleted.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> SET mykey "hello"
OK
ledis> EXPIRE mykey 60
(integer) 1
ledis> EXPIRE mykey 60
(integer) 1
ledis> TTL mykey
(integer) 58
ledis> PERSIST mykey
(integer) 1

EXPIREAT key timestamp

Set an expired unix timestamp on key.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> SET mykey "Hello"
OK
ledis> EXPIREAT mykey 1293840000
(integer) 1
ledis> EXISTS mykey
(integer) 0

TTL key

Returns the remaining time to live of a key that has a timeout. If the key was not set a timeout, -1 returns.

Return value

int64: TTL in seconds

Examples

ledis> SET mykey "hello"
OK
ledis> EXPIRE mykey 10
(integer) 1
ledis> TTL mykey
(integer) 8

PERSIST key

Remove the existing timeout on key

Return value

int64:

• 1 if the timeout was removed
• 0 if key does not exist or does not have an timeout

Examples

ledis> SET mykey "hello"
OK
ledis> EXPIRE mykey 60
(integer) 1
ledis> TTL mykey
(integer) 57
ledis> PERSIST mykey
(integer) 1
ledis> TTL mykey
(integer) -1

SCAN key [MATCH match] [COUNT count]

Iterate KV keys incrementally.

Key is the start for the current iteration. Match is the regexp for checking matched key. Count is the maximum retrieved elememts number, default is 10.

Return value

an array of two values, first value is the key for next iteration, second value is an array of elements.

Examples

ledis>set a 1
OK
ledis>set b 2
OK
ledis>set c 3
OK
127.0.0.1:6380>scan "" 
1) ""
2) ["a" "b" "c"]
ledis>scan "" count 1
1) "a"
2) ["a"]
ledis>scan "a" count 1
1) "b"
2) ["b"]
ledis>scan "b" count 1
1) "c"
2) ["c"]
ledis>scan "c" count 1
1) ""
2) []

Hash

HDEL key field [field ...]

Removes the specified fiedls from the hash stored at key.

Return value

int64: the number of fields that were removed from the hash.

Examples

ledis> HSET myhash field1 "foo"
(integer) 1
ledis> HDEL myhash field1 field2
(integer) 1

HEXISTS key field

Returns if field is an existing field in the hash stored at key.

Return value

int64:

• 1 if the hash contains field
• 0 if the hash does not contain field, or key does not exist.

Examples

ledis> HSET myhash field1 "foo"
(integer) 1
ledis> HEXISTS myhash field1 
(integer) 1
ledis> HEXISTS myhash field2
(integer) 0

HGET key field

Returns the value associated with field in the hash stored at key.

Return value

bulk: the value associated with field, or nil.

Examples

ledis> HSET myhash field1 "foo"
(integer) 1
ledis> HGET myhash field1
"foo"
ledis> HGET myhash field2
(nil)

HGETALL key

Returns all fields and values of the hash stored at key.

Return value

array: list of fields and their values stored in the hash, or an empty list (using nil in ledis-cli)

Examples

ledis> HSET myhash field1 "hello"
(integer) 1
ledis> HSET myhash field2 "world"
(integer) 1
ledis> HGETALL myhash
1) "field1"
2) "hello"
3) "field2"
4) "world"

HINCRBY key field increment

Increments the number stored at field in the hash stored at key by increment. If key does not exist, a new hash key is created. If field does not exists the value is set to 0 before incrementing.

Return value

int64: the value at field after the increment.

Examples

ledis> HINCRBY myhash field 1
(integer) 1
ledis> HGET myhash field
"1"
ledis> HINCRBY myhash field 5
(integer) 6
ledis> HINCRBY myhash field -10
(integer) -4

HKEYS key

Return all fields in the hash stored at key.

Return value

array: list of fields in the hash, or an empty list.

Examples

ledis> HSET myhash field1 "hello"
(integer) 1
ledis> HSET myhash field2 "world"
(integer) 1
ledis> HKEYS myhash
1) "field1"
2) "field2"

HLEN key

Returns the number of fields contained in the hash stored at key

Return value

int64: number of fields in the hash, or 0 when key does not exist.

Examples

ledis> HSET myhash field1 "hello"
(integer) 1
ledis> HSET myhash field2 "world"
(integer) 1
ledis> HLEN myhash
(integer) 2

HMGET key field [field ...]

Returns the values associated with the specified fields in the hash stored at key. If field does not exist in the hash, a nil value is returned.

Return value

array: list of values associated with the given fields.

Examples

ledis> HSET myhash field1 "hello"
(integer) 1
ledis> HSET myhash field2 "world"
(integer) 1
ledis> HMGET myhash field1 field2 nofield
1) "hello"
2) "world"
3) (nil)

HMSET key field value [field value ...]

Sets the specified fields to their respective values in the hash stored at key.

Return value

string: OK

Examples

ledis> HMSET myhash field1 "hello" field2 "world"
OK
ledis> HMGET myhash field1 field2
1) "hello"
2) "world"

HSET key field value

Sets field in the hash stored at key to value. If key does not exists, a new hash key is created.

Return value

int64:

• 1 if field is a new field in the hash and value was set.
• 0 if field already exists in the hash and the value was updated.

Examples

ledis> HSET myhash field1 "hello"
(integer) 1
ledis> HGET myhash field1
"hello"
ledis> HSET myhash field1 "world"
(integer) 0
ledis> HGET myhash field1
"world"

HVALS key

Returns all values in the hash stored at key.

Return value

array: list of values in the hash, or an empty list.

Examples

ledis> HSET myhash field1 "hello"
(integer) 1
ledis> HSET myhash field2 "world"
(integer) 1
ledis> HVALS myhash
1) "hello"
2) "world"

HCLEAR key

Deletes the specified hash key

Return value

int64: the number of fields in the hash stored at key

Examples

ledis> HMSET myhash field1 "hello" field2 "world"
OK
ledis> HCLEAR myhash
(integer) 2

HMCLEAR key [key...]

Deletes the specified hash keys.

Return value

int64: the number of input keys

Examples

ledis> HMSET myhash field1 "hello" field2 "world"
OK
ledis> HMCLEAR myhash
(integer) 1

HEXPIRE key seconds

Sets a hash key's time to live in seconds, like expire similarly.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> HSET myhash a  100
(integer) 1
ledis> HGET myhash a
100
ledis> HEXPIRE myhash 100
(integer) 1
ledis> HTTL myhash
(integer) 94
ledis> HPERSIST myhash
(integer) 1
ledis> HTTL myhash
(integer) -1
ledis> HEXPIRE not_exists_key 100
(integer) 0

HEXPIREAT key timestamp

Sets the expiration for a hash key as a unix timestamp, like expireat similarly.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> HSET myhash a  100
(integer) 1
ledis> HEXPIREAT myhash 1404999999
(integer) 1
ledis> HTTL myhash
(integer) 802475
ledis> HEXPIREAT not_exists_key  1404999999
(integer) 0

HTTL key

Returns the remaining time to live of a key that has a timeout. If the key was not set a timeout, -1 returns.

Return value

int64: TTL in seconds

Examples

ledis> HSET myhash a  100
(integer) 1
ledis> HEXPIREAT myhash 1404999999
(integer) 1
ledis> HTTL myhash
(integer) 802475
ledis> HTTL not_set_timeout
(integer) -1

HPERSIST key

Remove the expiration from a hash key, like persist similarly. Remove the existing timeout on key.

Return value

int64:

• 1 if the timeout was removed
• 0 if key does not exist or does not have an timeout

ledis> HSET myhash a  100
(integer) 1
ledis> HEXPIREAT myhash 1404999999
(integer) 1
ledis> HTTL myhash
(integer) 802475
ledis> HPERSIST myhash
(integer) 1
ledis> HTTL myhash
(integer) -1
ledis> HPERSIST not_exists_key
(integer) 0

HSCAN key [MATCH match] [COUNT count]

Iterate Hash keys incrementally.

See SCAN for more information.

List

LINDEX key index

Returns the element at index index in the list stored at key. The index is zero-based, so 0 means the first element, 1 the second element and so on. Negative indices can be used to designate elements starting at the tail of the list. Here, -1 means the last element, -2 means the penultimate and so forth. When the value at key is not a list, an error is returned.

Return value

string: the requested element, or nil when index is out of range.

Examples

ledis> RPUSH a 1 2 3
(integer) 3
ledis> LINDEX a 0
1
ledis> LINDEX a 1
2
ledis> LINDEX a 2
3
ledis> LINDEX a 3
(nil)
ledis> LINDEX a -1
3

LLEN key

Returns the length of the list stored at key. If key does not exist, it is interpreted as an empty list and 0is returned. An error is returned when the value stored at key is not a list.

Return value

int64: the length of the list at key.

Examples

ledis> RPUSH a 'foo'
(integer) 1
ledis> RPUSH a 'bar'
(integer) 2
ledis> LLEN a
(integer) 2

LPOP key

Removes and returns the first element of the list stored at key.

Return value

bulk: the value of the first element, or nil when key does not exist.

Examples

ledis> RPUSH a 'one'
(integer) 1
ledis> RPUSH a 'two'
(integer) 2
ledis> RPUSH a 'three'
(integer) 3
ledis> LPOP a
one

LRANGE key start stop

Returns the specified elements of the list stored at key. The offsets start and stop are zero-based indexes, with 0 being the first element of the list (the head of the list), 1 being the next element and so on.

Return value

array: list of elements in the specified range.

Examples

ledis> RPUSH a 'one' 'two' 'three'
(integer) 3
ledis> LRANGE a 0 0
1) "one"
ledis> LRANGE a -100 100
1) "one"
2) "two"
3) "three"
ledis> LRANGE a -3 2
1) "one"
2) "two"
3) "three"
ledis> LRANGE a 0 -1
(empty list or set)

LPUSH key value [value ...]

Insert all the specified values at the head of the list stored at key. If key does not exist, it is created as empty list before performing the push operations. When key holds a value that is not a list, an error is returned.

Return value

int64: the length of the list after the push operations.

Examples

ledis> LPUSH a 1
(integer) 1
ledis> LPUSH a 2
(integer) 2
ledis> LRANGE a 0 2
1) "2"
2) "1"

RPOP key

Removes and returns the last element of the list stored at key.

Return value

bulk: the value of the last element, or nil when key does not exist.

Examples

edis > RPUSH a 1
(integer) 1
ledis> RPUSH a 2
(integer) 2
ledis> RPUSH a 3
(integer) 3
ledis> RPOP a
3
ledis> LRANGE a 0 3
1) "1"
2) "2"

RPUSH key value [value ...]

Insert all the specified values at the tail of the list stored at key. If key does not exist, it is created as empty list before performing the push operation. When key holds a value that is not a list, an error is returned.

Return value

int64: the length of the list after the push operation.

Examples

ledis>  RPUSH a 'hello'
(integer) 1
ledis> RPUSH a 'world'
(integer) 2
ledis> LRANGE a 0 2
1) "hello"
2) "world"

LCLEAR key

Deletes the specified list key

Return value

int64: the number of values in the list stored at key

Examples

ledis> RPUSH a 1 2 3
(integer) 3
ledis> LLEN a
(integer) 3
ledis> LCLEAR a
(integer) 3
ledis> LLEN a
(integer) 0

LMCLEAR key [key ...]

Delete multiple keys from list

Return value

int64: the number of input keys

Examples

ledis> rpush a 1
(integer) 1
ledis> rpush b 2
(integer) 1
ledis> lmclear a b
(integer) 2

LEXPIRE key seconds

Set a timeout on key. After the timeout has expired, the key will be deleted.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> RPUSH a 1
(integer) 1
ledis> LEXPIRE a 100
(integer) 1
ledis> LTTL a
(integer) 96
ledis> LPERSIST a
(integer) 1
ledis> LTTL a
(integer) -1

LEXPIREAT key timestamp

Set an expired unix timestamp on key.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> RPUSH a 1
(integer) 1
ledis> LEXPIREAT a 1404140183
(integer) 1
ledis> LTTL a
(integer) 570
ledis> LPERSIST a
(integer) 1
ledis> LTTL a
(integer) -1
ledis>

LTTL key

Returns the remaining time to live of a key that has a timeout. If the key was not set a timeout, -1 returns.

Return value

int64: TTL in seconds

Examples

ledis> RPUSH a 1
(integer) 1
ledis> LEXPIREAT a 1404140183
(integer) 1
ledis> LTTL a
(integer) 570
ledis> LPERSIST a
(integer) 1
ledis> LTTL a
(integer) -1

LPERSIST key

Remove the existing timeout on key

Return value

int64:

• 1 if the timeout was removed
• 0 if key does not exist or does not have an timeout

Examples

ledis> RPUSH a 1
(integer) 1
ledis> LEXPIREAT a 1404140183
(integer) 1
ledis> LTTL a
(integer) 570
ledis> LPERSIST a
(integer) 1
ledis> LTTL a
(integer) -1
ledis> LPERSIST b
(integer) 0

LSCAN key [MATCH match] [COUNT count]

Iterate list keys incrementally.

See SCAN for more information.

Set

SADD key member [member ...]

Add the specified members to the set stored at key. Specified members that are already a member of this set are ignored. If key does not exist, a new set is created before adding the specified members.

Return value

int64: the number of elements that were added to the set, not including all the elements already present into the set.

Examples

ledis> SADD myset hello
(integer) 1
ledis> SADD myset world
(integer) 1
ledis> SADD myset hello
(integer) 0
ledis> SMEMBERS myset
1) "hello"
2) "world"

SCARD key

Returns the set cardinality (number of elements) of the set stored at key.

Return value

int64: the cardinality (number of elements) of the set, or 0 if key does not exist.

Examples

ledis> SADD myset hello
(integer) 1
ledis> SADD myset world
(integer) 1
ledis> SADD myset hello
(integer) 0
ledis> SCARD myset
(integer) 2

SDIFF key [key ...]

Returns the members of the set resulting from the difference between the first set and all the successive sets. For example:

key1 = {a,b,c,d}
key2 = {c}
key3 = {a,c,e}
SDIFF key1 key2 key3 = {b,d}

Keys that do not exist are considered to be empty sets.

Return value

bulk: list with members of the resulting set.

Examples

ledis> SADD key1 a b c 
(integer) 3
ledis> SADD key2 c d e
(integer) 3
ledis> SDIFF key1 key2
1) "a"
2) "b"
ledis> SDIFF key2 key1
1) "d"
2) "e"

SDIFFSTORE destination key [key ...]

This command is equal to SDIFF, but instead of returning the resulting set, it is stored in destination. If destination already exists, it is overwritten.

Return value

int64: the number of elements in the resulting set.

Examples

ledis> SADD key1 a b c 
(integer) 3
ledis> SADD key2 c d e
(integer) 3
ledis> SDIFF key1 key2
1) "a"
2) "b"
ledis> SDIFFSTORE key key1 key2
(integer) 2
ledis> SMEMBERS key
1) "a"
2) "b"

SINTER key [key ...]

Returns the members of the set resulting from the intersection of all the given sets. For example:

key1 = {a,b,c,d}
key2 = {c}
key3 = {a,c,e}
SINTER key1 key2 key3 = {c}

Keys that do not exist are considered to be empty sets. With one of the keys being an empty set, the resulting set is also empty (since set intersection with an empty set always results in an empty set).

Return value

bulk: list with members of the resulting set.

Examples

ledis> SADD key1 a b c 
(integer) 3
ledis> SADD key2 c d e
(integer) 3
ledis> SINTER key1 key2
1) "c"
ledis> SINTER key2 key_empty
(nil)

SINTERSTORE destination key [key ...]

This command is equal to SINTER, but instead of returning the resulting set, it is stored in destination. If destination already exists, it is overwritten.

Return value

int64: the number of elements in the resulting set.

Examples

ledis> SADD key1 a b c 
(integer) 3
ledis> SADD key2 c d e
(integer) 3
ledis> SINTERSTORE key key1 key2
(integer) 1
ledis> SMEMBERS key
1) "c"

SISMEMBER key member

Returns if member is a member of the set stored at key.

Return value

Int64 reply, specifically:

• 1 if the element is a member of the set.
• 0 if the element is not a member of the set, or if key does not exist.

Examples

ledis> SADD myset hello
(integer) 1
ledis> SISMEMBER myset hello
(integer) 1
ledis> SISMEMBER myset hell
(integer) 0

SMEMBERS key

Returns all the members of the set value stored at key. This has the same effect as running SINTER with one argument key.

Return value

bulk: all elements of the set.

Examples

ledis> SADD myset hello
(integer) 1
ledis> SADD myset world
(integer) 1
ledis> SMEMBERS myset
1) "hello"
2) "world"

SREM key member [member ...]

Remove the specified members from the set stored at key. Specified members that are not a member of this set are ignored. If key does not exist, it is treated as an empty set and this command returns 0.

Return value

int64: the number of members that were removed from the set, not including non existing members.

Examples

ledis> SADD myset one
(integer) 1
ledis> SADD myset two
(integer) 1
ledis> SADD myset three
(integer) 1
ledis> SREM myset one
(integer) 1
ledis> SREM myset four
(integer) 0
ledis> SMEMBERS myset
1) "three"
2) "two"

SUNION key [key ...]

Returns the members of the set resulting from the union of all the given sets. For example:

key1 = {a,b,c,d}
key2 = {c}
key3 = {a,c,e}
SUNION key1 key2 key3 = {a,b,c,d,e}

Keys that do not exist are considered to be empty sets.

Return value

bulk: list with members of the resulting set.

Examples

ledis> SMEMBERS key1
1) "a"
2) "b"
3) "c"
ledis> SMEMBERS key2
1) "c"
2) "d"
3) "e"
ledis> SUNION key1 key2
1) "a"
2) "b"
3) "c"
4) "d"
5) "e"

SUNIONSTORE destination key [key]

This command is equal to SUNION, but instead of returning the resulting set, it is stored in destination. If destination already exists, it is overwritten.

Return value

int64: the number of elements in the resulting set.

Examples

ledis> SMEMBERS key1
1) "a"
2) "b"
3) "c"
ledis> SMEMBERS key2
1) "c"
2) "d"
3) "e"
ledis> SUNIONSTORE key key1 key2
(integer) 5
ledis> SMEMBERS key
1) "a"
2) "b"
3) "c"
4) "d"
5) "e"

SCLEAR key

Deletes the specified set key

Return value

int64: the number of fields in the hash stored at key

Examples

ledis> SMEMBERS key
1) "a"
2) "b"
3) "c"
4) "d"
5) "e"
ledis> SCLEAR key
(integer) 5

SMCLEAR key [key ...]

Deletes the specified set keys.

Return value

int64: the number of input keys

Examples

ledis> SMCLEAR key1 key2
(integer) 2
ledis> SMCLEAR em1 em2
(integer) 2

SEXPIRE key seconds

Sets a set key’s time to live in seconds, like expire similarly.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> SADD key 1 2 
(integer) 2
ledis> SEXPIRE key 100
(integer) 1
ledis> STTL key
(integer) 95

SEXPIREAT key timestamp

Sets the expiration for a set key as a unix timestamp, like expireat similarly.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> SADD key 1 2 
(integer) 2
ledis> SEXPIREAT key 1408094999
(integer) 1
ledis> STTL key
(integer) 908

STTL key

Returns the remaining time to live of a key that has a timeout. If the key was not set a timeout, -1 returns.

Return value

int64: TTL in seconds

Examples

ledis> SADD key 1 2 
(integer) 2
ledis> SEXPIREAT key 1408094999
(integer) 1
ledis> STTL key
(integer) 908

SPERSIST key

Remove the expiration from a set key, like persist similarly. Remove the existing timeout on key.

Return value

int64:

• 1 if the timeout was removed
• 0 if key does not exist or does not have an timeout

Examples

ledis> SEXPIREAT key 1408094999
(integer) 1
ledis> STTL key
(integer) 908
ledis> SPERSIST key
(integer) 1
ledis> STTL key
(integer) -1

SSCAN key [MATCH match] [COUNT count]

Iterate Set keys incrementally.

See SCAN for more information.

ZSet

ZADD key score member [score member ...]

Adds all the specified members with the specified scores to the sorted set stored at key. It is possible to specify multiple score / member pairs. If a specified member is already a member of the sorted set, the score is updated and the element reinserted at the right position to ensure the correct ordering.

If key does not exist, a new sorted set with the specified members as sole members is created, like if the sorted set was empty. If the key exists but does not hold a sorted set, an error is returned.

The score values should be the string representation of an int64 number. +inf and -inf values are valid values as well.

Currently, we only support int64 type, not double type.

Return value

int64, specifically:

The number of elements added to the sorted sets, not including elements already existing for which the score was updated.

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZADD myzset 1 'uno'
(integer) 1
ledis> ZADD myzset 2 'two' 3 'three'
(integer) 2
ledis> ZRANGE myzset 0 -1 WITHSCORES
1) "one"
2) "1"
3) "uno"
4) "1"
5) "two"
6) "2"
7) "three"
8) "3"

ZCARD key

Returns the sorted set cardinality (number of elements) of the sorted set stored at key.

Return value

int64: the cardinality (number of elements) of the sorted set, or 0 if key does not exist.

Examples

edis > ZADD myzset 1 'one'
(integer) 1
ledis> ZADD myzset 1 'uno'
(integer) 1
ledis> ZADD myzset 2 'two' 3 'three'
(integer) 2
ledis> ZRANGE myzset 0 -1 WITHSCORES
1) "one"
2) "1"
3) "uno"
4) "1"
5) "two"
6) "2"
7) "three"
8) "3"
ledis> ZCARD myzset
(integer) 4

ZCOUNT key min max

Returns the number of elements in the sorted set at key with a score between min and max. The min and max arguments have the same semantic as described for ZRANGEBYSCORE.

Return value

int64: the number of elements in the specified score range.

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZADD myzset 1 'uno'
(integer) 1
ledis> ZADD myzset 2 'two' 3 'three'
(integer) 2
ledis> ZRANGE myzset 0 -1 WITHSCORES
1) "one"
2) "1"
3) "uno"
4) "1"
5) "two"
6) "2"
7) "three"
8) "3"
ledis> ZCOUNT myzset -inf +inf
(integer) 4
ledis> ZCOUNT myzset (1 3
(integer) 2

ZINCRBY key increment member

Increments the score of member in the sorted set stored at key by increment. If member does not exist in the sorted set, it is added with increment as its score (as if its previous score was 0). If key does not exist, a new sorted set with the specified member as its sole member is created. An error is returned when key exists but does not hold a sorted set. The score value should be the string representation of a numeric value. It is possible to provide a negative value to decrement the score.

Return value

bulk: the new score of member (an int64 number), represented as string.

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZADD myzset 2 'two'
(integer) 1
ledis> ZINCRBY myzset 2 'one'
3
ledis> ZRANGE myzset 0 -1 WITHSCORES
1) "two"
2) "2"
3) "one"
4) "3"

ZRANGE key start stop [WITHSCORES]

Returns the specified range of elements in the sorted set stored at key. The elements are considered to be ordered from the lowest to the highest score. Lexicographical order is used for elements with equal score.

Return value

array: list of elements in the specified range (optionally with their scores).

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZADD myzset 2 'two'
(integer) 1
ledis> ZADD myzset 3 'three'
(integer) 1
ledis> ZRANGE myzset 0 -1
1) "one"
2) "two"
3) "three"
ledis> ZRANGE myzset 2 3
1) "three"
ledis> ZRANGE myzset -2 -1
1) "two"
2) "three"

ZRANGEBYSCORE key min max [WITHSCORES] [LIMIT offset count]

Returns all the elements in the sorted set at key with a score between min and max (including elements with score equal to min or max). The elements are considered to be ordered from low to high scores.

Exclusive intervals and infinity

min and max can be -inf and +inf, so that you are not required to know the highest or lowest score in the sorted set to get all elements from or up to a certain score. By default, the interval specified by min and max is closed (inclusive). It is possible to specify an open interval (exclusive) by prefixing the score with the character (. For example:

ZRANGEBYSCORE zset (1 5

Will return all elements with 1 < score <= 5 while:

ZRANGEBYSCORE zset (5 (10

Will return all the elements with 5 < score < 10 (5 and 10 excluded).

Return value

array: list of elements in the specified score range (optionally with their scores).

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZADD myzset 2 'two'
(integer) 1
ledis> ZADD myzset 3 'three'
(integer) 1
ledis> ZRANGEBYSCORE myzset -inf +inf WITHSCORES
1) "one"
2) "1"
3) "two"
4) "2"
5) "three"
6) "3"
ledis> ZRANGEBYSCORE myzset -inf +inf WITHSCORES LIMIT  2 5
1) "three"
2) "3"
ledis> ZRANGEBYSCORE myzset (1 2 WITHSCORES
1) "two"
2) "2"
ledis> ZRANGEBYSCORE myzset (1 (2 WITHSCORES

ZRANK key member

Returns the rank of member in the sorted set stored at key, with the scores ordered from low to high. The rank (or index) is 0-based, which means that the member with the lowest score has rank 0.

Return value

Return value

• If member exists in the sorted set, Integer reply: the rank of member.
• If member does not exist in the sorted set or key does not exist, Bulk string reply: nil.

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZADD myzset 2 'two'
(integer) 1
ledis> ZADD myzset 3 'three'
(integer) 1
ledis> ZRANGEBYSCORE  myzset -inf +inf WITHSCORES
1) "one"
2) "1"
3) "two"
4) "2"
5) "three"
6) "3"
ledis> ZRANK myzset 'three'
(integer) 2

ZREM key member [member ...]

Removes the specified members from the sorted set stored at key. Non existing members are ignored. An error is returned when key exists and does not hold a sorted set.

Return value

int64 reply, specifically:

The number of members removed from the sorted set, not including non existing members.

Examples

ledis> ZADD myzset 1 one 2 two 3 three 4 four
(integer) 3
ledis> ZRANGE myzset 0 -1
1) "one"
2) "two"
3) "three"
4) "four"
ledis> ZREM myzset three
(integer) 1
ledis> ZREM myzset one four three
(integer) 2

ZREMRANGEBYRANK key start stop

Removes all elements in the sorted set stored at key with rank between start and stop. Both start and stop are 0 -based indexes with 0 being the element with the lowest score. These indexes can be negative numbers, where they indicate offsets starting at the element with the highest score. For example: -1 is the element with the highest score, -2 the element with the second highest score and so forth.

Return value

int64: the number of elements removed.

Examples

ledis> ZADD myzset 1 one 2 two 3 three 4 four
(integer) 3
ledis> ZREMRANGEBYRANK myzset 0 2
(integer) 3
ledis> ZRANGE myzset 0 -1 WITHSCORES
1) "four"
2) "4"

ZREMRANGEBYSCORE key min max

Removes all elements in the sorted set stored at key with a score between min and max (inclusive). Min and max can be exclusive, following the syntax of ZRANGEBYSCORE.

Return value

int64: the number of elements removed.

Examples

ledis> ZADD myzset 1 one 2 two 3 three 4 four
(integer) 4
ledis> ZREMRANGEBYSCORE myzset -inf (2
(integer) 1
ledis> ZRANGE myzset 0 -1 WITHSCORES
1) "two"
2) "2"
3) "three"
4) "3"
5) "four"
6) "4"

ZREVRANGE key start stop [WITHSCORES]

Returns the specified range of elements in the sorted set stored at key. The elements are considered to be ordered from the highest to the lowest score. Descending lexicographical order is used for elements with equal score. Apart from the reversed ordering, ZREVRANGE is similar to ZRANGE.

Return value

array: list of elements in the specified range (optionally with their scores).

Examples

ledis> ZADD myzset 1 one 2 two 3 three 4 four
(integer) 4
ledis> ZREVRANGE myzset 0 -1
1) "four"
2) "three"
3) "two"
4) "one"

ZREVRANGEBYSCORE key max min [WITHSCORES] [LIMIT offset count]

Returns all the elements in the sorted set at key with a score between max and min (including elements with score equal to max or min). In contrary to the default ordering of sorted sets, for this command the elements are considered to be ordered from high to low scores. The elements having the same score are returned in reverse lexicographical order. Apart from the reversed ordering, ZREVRANGEBYSCORE is similar to ZRANGEBYSCORE.

Return value

array: list of elements in the specified score range (optionally with their scores).

Examples

ledis>  ZADD myzset 1 one 2 two 3 three 4 four
(integer) 4
ledis> ZREVRANGEBYSCORE myzset +inf -inf
1) "four"
2) "three"
3) "two"
4) "one"
ledis> ZREVRANGEBYSCORE myzset 2 1
1) "two"
2) "one"
ledis> ZREVRANGEBYSCORE myzset 2 (1
1) "two"
ledis> ZREVRANGEBYSCORE myzset (2 (1
(empty list or set)
ledis> ZREVRANGEBYSCORE myzset +inf -inf WITHSCORES LIMIT 1 2
1) "three"
2) "3"
3) "two"
4) "2"

ZREVRANK key member

Returns the rank of member in the sorted set stored at key, with the scores ordered from high to low. The rank (or index) is 0-based, which means that the member with the highest score has rank 0. Use ZRANK to get the rank of an element with the scores ordered from low to high.

Return value

• If member exists in the sorted set, Integer reply: the rank of member.
• If member does not exist in the sorted set or key does not exist, Bulk string reply: nil.

Examples

ledis> ZADD myzset 1 one
(integer) 1
ledis> ZADD myzset 2 two
(integer) 1
ledis> ZREVRANK myzset one
(integer) 1
ledis> ZREVRANK myzset three
(nil)

ZSCORE key member

Returns the score of member in the sorted set at key. If member does not exist in the sorted set, or key does not exist, nil is returned.

Return value

bulk: the score of member (an int64 number), represented as string.

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZSCORE myzset 'one'
1

ZCLEAR key

Delete the specified key

Return value

int64: the number of members in the zset stored at key

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZADD myzset 2 'two'
(integer) 1
ledis> ZADD myzset 3 'three'
(integer) 1
ledis> ZRANGE myzset 0 -1
1) "one"
2) "two"
3) "three"
ledis> ZCLEAR myzset
(integer) 3

ZMCLEAR key [key ...]

Delte multiple keys one time.

Return value

int64: the number of input keys

Examples

ledis> ZADD myzset1 1 'one'
(integer) 1
ledis> ZADD myzset2 2 'two'
(integer) 1
ledis> ZMCLEAR myzset1 myzset2
(integer) 2

ZEXPIRE key seconds

Set a timeout on key. After the timeout has expired, the key will be deleted.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZEXPIRE myzset 100
(integer) 1
ledis> ZTTL myzset
(integer) 97
ledis> ZPERSIST myzset
(integer) 1
ledis> ZTTL mset
(integer) -1
ledis> ZEXPIRE myzset1 100
(integer) 0

ZEXPIREAT key timestamp

Set an expired unix timestamp on key. Similar to ZEXPIRE.

Return value

int64:

• 1 if the timeout was set
• 0 if key does not exist or the timeout could not be set

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZEXPIREAT myzset 1404149999
(integer) 1
ledis> ZTTL myzset
(integer) 7155
ledis> ZPERSIST myzset
(integer) 1
ledis> ZTTL mset
(integer) -1
ledis> ZEXPIREAT myzset1 1404149999
(integer) 0

ZTTL key

Returns the remaining time to live of a key that has a timeout. If the key was not set a timeout, -1 returns.

Return value

int64: TTL in seconds

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZEXPIRE myzset 100
(integer) 1
ledis> ZTTL myzset
(integer) 97
ledis> ZTTL myzset2
(integer) -1

ZPERSIST key

Remove the existing timeout on key.

Return value

int64:

• 1 if the timeout was removed
• 0 if key does not exist or does not have an timeout

Examples

ledis> ZADD myzset 1 'one'
(integer) 1
ledis> ZEXPIRE myzset 100
(integer) 1
ledis> ZTTL myzset
(integer) 97
ledis> ZPERSIST myzset
(integer) 1
ledis> ZTTL mset
(integer) -1

ZUNIONSTORE destination numkeys key [key ...] [WEIGHTS weight [weight ...]] [AGGREGATE SUM|MIN|MAX]

Computes the union of numkeys sorted sets given by the specified keys, and stores the result in destination. It is mandatory to provide the number of input keys (numkeys) before passing the input keys and the other (optional) arguments.

By default, the resulting score of an element is the sum of its scores in the sorted sets where it exists. Using the WEIGHTS option, it is possible to specify a multiplication factor for each input sorted set. This means that the score of every element in every input sorted set is multiplied by this factor before being passed to the aggregation function. When WEIGHTS is not given, the multiplication factors default to 1.

With the AGGREGATE option, it is possible to specify how the results of the union are aggregated. This option defaults to SUM, where the score of an element is summed across the inputs where it exists. When this option is set to either MIN or MAX, the resulting set will contain the minimum or maximum score of an element across the inputs where it exists.

If destination already exists, it is overwritten.

Return value

int64: the number of elements in the resulting sorted set at destination.

Examples

ledis> ZADD zset1 1 "one"
(interger) 1
ledis> ZADD zset1 2 "two"
(interger) 1
ledis> ZADD zset2 1 "one"
(interger) 1
ledis> ZADD zset2 2 "two"
(interger) 1
ledis> ZADD zset2 3 "three"
(interger) 1
ledis> ZUNIONSTORE out 2 zset1 zset2 WEIGHTS 2 3
(interger) 3
ledis> ZRANGE out 0 -1 WITHSCORES
1) "one"
2) "5"
3) "three"
4) "9"
5) "two"
6) "10"

ZINTERSTORE destination numkeys key [key ...] [WEIGHTS weight [weight ...]] [AGGREGATE SUM|MIN|MAX]

Computes the intersection of numkeys sorted sets given by the specified keys, and stores the result in destination. It is mandatory to provide the number of input keys (numkeys) before passing the input keys and the other (optional) arguments.

By default, the resulting score of an element is the sum of its scores in the sorted sets where it exists. Because intersection requires an element to be a member of every given sorted set, this results in the score of every element in the resulting sorted set to be equal to the number of input sorted sets.

For a description of the WEIGHTS and AGGREGATE options, see ZUNIONSTORE.

If destination already exists, it is overwritten.

Return value

int64: the number of elements in the resulting sorted set at destination.

Examples

ledis> ZADD zset1 1 "one"
(interger) 1
ledis> ZADD zset1 2 "two"
(interger) 1
ledis> ZADD zset2 1 "one"
(interger) 1
ledis> ZADD zset2 2 "two"
(interger) 1
ledis> ZADD zset2 3 "three"
(interger) 1
ledis> ZINTERSTORE out 2 zset1 zset2 WEIGHTS 2 3
(interger) 3
ledis> ZRANGE out 0 -1 WITHSCORES
1) "one"
2) "5"
3) "two"
4) "10"

ZSCAN key [MATCH match] [COUNT count]

Iterate ZSet keys incrementally.

See SCAN for more information.

Bitmap

BGET key

Returns the whole binary data stored at key.

Return value

bulk: the raw value of key, or nil when key does not exist.

Examples

ledis> BMSETBIT flag 0 1 5 1 6 1
(integer) 3
ledis> BGET flag
a

BGETBIT key offset

Returns the bit value at offset in the string value stored at key. When offset beyond the data length, ot the target data is not exist, the bit value will be 0 always.

Return value

int64 : the bit value stored at offset.

Examples

ledis> BSETBIT flag 1024 1
(integer) 0
ledis> BGETBIT flag 0
(integer) 0
ledis> BGETBIT flag 1024
(integer) 1
ledis> BGETBIT flag 65535
(integer) 0

BSETBIT key offset value

Sets or clear the bit at offset in the binary data sotred at key. The bit is either set or cleared depending on value, which can be either 0 or 1. The offset argument is required to be qual to 0, and smaller than 2^23 (this means bitmap limits to 8MB).

Return value

int64 : the original bit value stored at offset.

Examples

ledis> BSETBIT flag 0 1
(integer) 0
ledis> BSETBIT flag 0 0
(integer) 1
ledis> BGETBIT flag 0 99
ERR invalid command param

BMSETBIT key offset value [offset value ...]

Sets the given offset to their respective values.

Return value

int64 : The number of input offset

Examples

ledis> BMSETBIT flag 0 1 1 1 2 0 3 1
(integer) 4
ledis> BCOUNT flag
(integer) 3

BOPT operation destkey key [key ...]

Perform a bitwise operation between multiple keys (containing string values) and store the result in the destination key.

Return value

Int64: The size of the string stored in the destination key, that is equal to the size of the longest input string. Examples

ledis> BMSETBIT a 0 1 2 1
(integer) 2
ledis> BMSETBIT b 1 1 
(integer) 1
ledis> BOPT AND res a b    
(integer) 3
ledis> BCOUNT res
(integer) 0
ledis> BOPT OR res2 a b
(integer) 3
ledis> BCOUNT res2
(integer) 3
ledis> BOPT XOR res3 a b
(integer) 3
ledis> BCOUNT res3
(integer) 3

BCOUNT key [start end]

Count the number of set bits in a bitmap.

Return value

int64 : The number of bits set to 1.

Examples

ledis> BMSETBIT flag 0 1 5 1 6 1
(integer) 3
ledis> BGET flag
a
ledis> BCOUNT flag
(integer) 3
ledis> BCOUNT flag 0 0s
(integer) 1
ledis> BCOUNT flag 0 4
(integer) 1
ledis> BCOUNT flag 0 5
(integer) 2
ledis> BCOUNT flag 5 6
(integer) 2

BEXPIRE key seconds

(refer to EXPIRE api for other types)

BEXPIREAT key timestamp

(refer to EXPIREAT api for other types)

BTTL key

(refer to TTL api for other types)

BPERSIST key

(refer to PERSIST api for other types)

BSCAN key [MATCH match] [COUNT count]

Iterate Bitmap keys incrementally.

See SCAN for more information.

Replication

SLAVEOF host port

Changes the replication settings of a slave on the fly. If the server is already acting as slave, SLAVEOF NO ONE will turn off the replication.

SLAVEOF host port will make the server a slave of another server listening at the specified host and port.

If a server is already a slave of a master, SLAVEOF host port will stop the replication against the old and start the synchronization against the new one, discarding the old dataset.

FULLSYNC

Inner command, starts a fullsync from the master set by SLAVEOF.

FULLSYNC will first try to sync all data from the master, save in local disk, then discard old dataset and load new one.

Return value

Examples

SYNC index offset

Inner command, syncs the new changed from master set by SLAVEOF at offset in binlog.index file.

Return value

Examples

Server

PING

Returns PONG. This command is often used to test if a connection is still alive, or to measure latency.

Return value

String

Examples

ledis> PING
PONG
ledis> PING
dial tcp 127.0.0.1:6665: connection refused
ledis>

ECHO message

Returns message.

Return value

bulk string reply

Examples

ledis> ECHO "hello"
hello

SELECT index

Select the DB with having the specified zero-based numeric index. New connections always use DB 0. Currently, We support 16 DBs(0-15).

Return value

Simple string reply

Examples

ledis> SELECT 2
OK
ledis> SELECT 15
OK
ledis> SELECT 16
ERR invalid db index 16

Transaction

BEGIN

Marks the start of a transaction block. Subsequent commands will be in a transaction context util using COMMIT or ROLLBACK.

You must known that BEGIN will block any other write operators before you COMMIT or ROLLBACK. Don't use long-time transaction.

Return value

Returns OK if the backend store engine in use supports transaction, otherwise, returns Err.

Examples

ledis> BEGIN
OK
ledis> SET HELLO WORLD
OK
ledis> COMMIT
OK

ROLLBACK

Discards all the changes of previously commands in a transaction and restores the connection state to normal.

Return value Returns OK if in a transaction context, otherwise, Err

Examples

ledis> BEGIN
OK
ledis> SET HELLO WORLD
OK
ledis> GET HELLO
"WORLD"
ledis> ROLLBACK
OK
ledis> GET HELLO
(nil)

COMMIT

Persists the changes of all the commands in a transaction and restores the connection state to normal.

Return value Returns OK if in a transaction context, otherwise, Err

Examples

ledis> BEGIN
OK
ledis> SET HELLO WORLD
OK
ledis> GET HELLO
"WORLD"
ledis> COMMIT
OK
ledis> GET HELLO
"WORLD"

Thanks doctoc