DOKK Library

REDIS cheatsheet [v1.0]

Authors Mason Jones

License CC-BY-NC-SA-3.0

Plaintext
                                          REDIS cheatsheet [v1.0]
                          starting the server                                    cd redis; ./redis-server
                           running the client                                       ./redis-cli <command>

                                           commands
                                                                      Test if specified key exists.
                                           exists key                 Return: 1 if exists, 0 if not
                                                                      Remove the specified keys.
                                  del key1 key2 ... keyN              Return: integer > 0 if keys removed, 0 if none of the keys existed
                                                                      Return the type of the value stored at key, as a string.
                                             type key                 Return: "none", "string", "list", "set"
                                                                      Return all keys matching pattern. Ex: keys h*llo, keys h?llo, keys h[aeo]llo
                                          keys pattern                Return: bulk reply string with keys separated by spaces
                                                                      Return a randomly-selected key from the current database.
                                            randomkey                 Return: the selected key, or empty string if database is empty
generic commands for all types




                                                                      Atomically renames key. Note: If newkey exists it is overwritten.
                                    rename oldkey newkey              Return: 1 if OK, 0 if oldkey doesn't exist or if it equals newkey
                                                                      Atomically renames key, fails if newkey exists.
                                  renamenx oldkey newkey              Return: 1 if OK, 0 if newkey exists, if oldkey doesn't exist or if it equals newkey
                                                                      Returns the number of keys in the current database.
                                              dbsize                  Return: integer, the number of keys
                                    expire key seconds                Sets timeout on the specified key.
                                   expireat key unixtime              Return: 1 if timeout set, 0 if key already has a timeout or doesn't exist
                                                                      Returns remaining time to live, in seconds, for a key with EXPIRE set.
                                             ttl key                  Return: integer number of seconds, or -1 if key doesn't exist or has no expiration
                                                                      Selects a database by index (zero-based). Default database is 0.
                                       select db-index                Return: 1 if OK, 0 if error
                                                                      Moves a key from current database to specified database.
                                      move key db-index               Return: 1 if OK, 0 if key doesn't exist or is already present in the target database
                                                                      Deletes all keys in the currently-selected database.
                                             flushdb                  Return: 1 -- this command never fails
                                                                      Deletes all keys in all existing databases.
                                             flushall                 Return: 1 -- this command never fails


                                        set key value                 Sets the value of key to the string value; setnx will not overwrite an existing value.
                                       setnx key value                Return: 1 if OK, 0 if error
                                                                      Gets the value of key.
                                             get key                  Return: string value if OK, "nil" if key does not exist
commands for strings




                                                                      Atomically sets the value of key to the string value and returns old value of key.
                                       getset key value               Return: value of key prior to the new value being set ("nil" if key did not exist)
                                                                      Gets the values of all specified keys.
                                  mget key1 key2 ... keyN             Return: multi-bulk reply of all values, with "nil" for any keys that do not exist

                                  mset key1 value1 ... keyN valueN Sets the values of the keys to the string values; msetnx will not overwrite existing
                                 msetnx key1 value1 ... keyN valueN values if any key exists. Return: 1 if all keys were set, 0 if none were set

                                             incr key                 Increments/decrements value of key by 1.
                                             decr key                 Return: New value after increment/decrement operation
                                     incrby key integer               Increments/decrements value of key by the integer value specified.
                                     decrby key integer               Return: New value after increment/decrement operation
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                                    rpush key string               Adds the string to the head (rpush) or tail (lpush) of the list at key.
                                    lpush key string               Return: 1 if exists, 0 if key exists but is not a list
                                                                   Returns the length of the list at key.
                                          llen key                 Return: integer length, or error if key is not a list
                                                                   Returns the elements of list at key, zero-based. Negative numbers are offset from
                                 lrange key start end              the end of the list. Return: requested elements or empty list if no match
 commands operating on lists




                                                                   Trims list at key to contain only the specified elements.
                                  ltrim key start end              Return: 1 if OK, error if key is not a list
                                                                   Returns the element at the specified index of the list key.
                                    lindex key index               Return: the requested item; empty string if no such element; error if key isn't a list
                                                                   Sets the element of list key at index to the specified value.
                                 lset key index value              Return: 1 if OK, error if index out of range or key isn't a list
                                                                   Removes count number of items from the list that have the specified value. Count
                                 lrem key count value              0 will remove all; negative count starts from the end. Return: # items removed
                                     lpop key string               Atomically removes and returns the first (lpop) or last (rpop) element from list
                                     rpop key string               key. Return: the element, or "nil" if empty/nonexistent list; error if key isn't a list
                                 blpop key1...keyN timeout         Blocking pop, returns when a specified list contains an element.
                                 brpop key1...keyN timeout         Return: key and popped value, or "nil" if operation times out
                                                                   Atomically returns last element from srckey and pushes as first element to
                               rpoplpush srckey destkey destkey. Return: element popped/pushed, or "nil" if srckey empty or nonexistent

                                                                   Adds member to the set stored at key.
                                     sadd key member               Return: 1 if OK, 0 if element was already a set member; error if key isn't a set
                                                                   Removes member from set key.
                                     srem key member               Return: 1 if OK, 0 element not a set member; error if key isn't a set
                                        spop key                   Returns random element from set key. spop will remove the element.
                                     srandmember key               Return: element, or nil object if key is empty or doesn't exist
commands operating on sets




                                                                   Atomically moves member from set srckey to set dstkey.
                               smove srckey dstkey member
                                                                   Return: 1 if OK, 0 if element not found in srckey; error if either key isn't a set
                                                                   Returns the number of elements in set key.
                                         scard key                 Return: integer number of elements; 0 if empty or key doesn't exist
                                                                   Return whether member is in set key.
                                 sismember key member              Return: 1 if element is a member, 0 if not or if key doesn't exist

                                  sinter key1 key2...keyN     Returns the members resulting from intersection of sets specified. sinterstore will
                               sinterstore dstkey key1...keyN store results in new set and return status code.

                                  sunion key1 key2...keyN     Returns the members resulting from union of sets specified. sunionstore will store
                               sunionstore dstkey key1...keyN results in new set and return status code.

                                  sdiff key1 key2...keyN           Returns the members resulting from the difference between the first set and the
                               sdiffstore dstkey key1...keyN       rest. sdiffstore will store results in new set and return status code.
                                                                   Returns all of the members of set key. This is sinter, for only one set.
                                       smembers key                Return: the members

                       sort         key [by pattern] [limit start count] [get pattern] [asc|desc] [alpha] [store dstkey]
          Sorts the elements in the list, set, or sorted set at key. Default sort is numeric, ascending. Specifying asc or desc will sort in ascending or
          descending order. Specifying alpha will sort alphabetically. limit will return count number of elements beginning at offset start (zero-
          based). store will put the results of the sort into a list with key dstkey.

          Specifying "by pattern" will sort using the values at keys generated using the pattern. For example, if the list/set being sorted contains the
          values 1, 2, 3 then "sort by weight_*" will sort using the values at keys "weight_1", "weight_2", "weight_3".

          Specifying "get pattern" will retrieve the values stored at keys generated using the pattern. For example, "get items_*" will return the
          values at keys items_1, items_2, items_3 if the list/set being sorted contains the values 1, 2, 3.
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                                                                     Adds member to zset key, with specified score.
                                     zadd key score member           Return: 1 if added, 0 if element was already a member and score was updated
                                                                     Removes member from zset key.
                                        zrem key member
commands operating on sorted sets



                                                                     Return: 1 if removed, 0 if element was not a member
                                                                     Increments score of member by incr and updates element's position in zset.
                                    zincrby key incr member          Return: integer, the new score of member after the increment
                                      zrange key start end           Returns elements in zset key within the specified index range, sorted in order (or
                                     zrevrange key start end         reverse with zrevrange). Option: "withscores" will also return scores.
                                    zrangebyscore key min max        Returns elements in zset key with scores within the specified range.
                                      [limit offset count]           Option: "withscores" will also return scores.
                                     zremrangebyscore key            Removes elements from zset key with scores between min and max.
                                           min max                   Return: integer, number of elements removed
                                                                     Returns the number of elements in the zset key.
                                           zcard key                 Return: integer, the number of elements; returns 0 if key doesn't exist
                                                                     Returns the score of the specified element in zset key.
                                      zscore key element             Return: the score, as a string; or "nil" if key or element don't exist


                                                                     Saves all databases to disk. Connection requests will not be served during the
                                              save                   save. Returns OK when complete.
                                                                     Saves all databases to disk in the background. Redis forks and writes so the
                                             bgsave                  parent process continues to process connection requests.
                                                                     Returns integer unix time of last successful save. This can be used following a
                                            lastsave
persistence and control commands




                                                                     bgsave to check if it was successful.

                                         bgrewriteaof                Rewrites the Append Only File in the background.


                                            shutdown                 Stops all clients, saves databases, and quits.


                                              info                   Returns information and statistics about the server.

                                                                     Used to enter commands for debugging. Telnet to redis server then enter
                                            monitor                  monitor command. Enter quit to end the session.
                                       slaveof host port             Makes server the replication slave of the redis server at host/port. The "no one"
                                        slaveof no one               form turns off replication, making the server a master.

                                              quit                   Tells server to close the connection immediately.

                                                                     Authorizes client using the provided password, if redis server is configured with
                                         auth password               requirepass. Returns OK or error if password is incorrect.


            redis site: http://code.google.com/p/redis/
            mailing list: http://groups.google.com/group/redis-db




                                             redis cheat sheet v1.0 by mason jones, mar.2010          http://masonoise.wordpress.com
                                                   Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License