All commands can be found in Redis Website

Commands

Basic key value pair

SET {varname} {value} // sets a variable

SET foo 100

GET {varname} // gets a value

GET foo
// returns "100"

INCR {varname} // increments a variable

INCR foo
GET foo
// returns "101"

DECR {varname} // decrements a variable

INCR foo
GET foo
// returns "101"

EXISTS {varname} // returns 1 if variable exists, else 0

EXISTS foo
// returns 1 (integer)

DEL {varname} // deletes a variable

SET bar 250
DEL bar
GET bar
// returns (nil)

FLUSHALL // deletes all variables

FLUSHALL 
GET foo
// returns (nil)

EXPIRE {varname} // adds TTL (in seconds) to a variables

SET foo 100
EXPIRE FOO 10
GET foo
// returns 100

TTL {varname} // gets the TTL (in seconds) for a variable. If the value is -2 it is expired. -1 means it never expires

TTL foo
// depending on when we set the EXPIRE, result will for example give 2 (integer) if it has passed 8 seconds from above

SETEX {varname} {ttl} {value} //sets a value with expiration

SETEX foo 30 "Hello world"

PERSIST {varname} // removes TTL in a variable

PERSIST foo

MSET { {varname} {value} } {...} //multiple setting of variables

MSET key1 "Hello" key2 "World"

APPEND {varname} {value} // appends values to the variables

APPEND key1 " World"
GET key1
// returns "Hello World"

RENAME {varname} {new name} // change a variable name

RENAME key1 greetings

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Data Types

String

As seen above, strings act like normal string in any language

integer

As seen above, strings act like normal string in any language

List

List is basically an array of strings ordered by insertion. We can push to the Head (left) or the tail (right) of both array ends.

LPUSH {listname} {value} // adds a value at the head of the list

RPUSH {listname} {value} // adds a value at the tail of the list

LPUSH mylist a // list is now "a"
LPUSH mylist b // list is now "b","a"
RPUSH mylist c // list is now "b","a", "c"

LRANGE {listname} {From Index} {To Index} // gets the values from a list from index to the next index

LRANGE mylist 1 -1
//gets all items starting at index 1
LRANGE mylist 0 1
// gets values from index 0 to 1

LLEN {listname} // gives the size/length of array

LLEN mylist
// returns 3

LPOP {listname} // pops item out of a list from the left (head)

RPOP {listname} // pops item out of a list from the right (tail)

LPOP mylist
// returns 'b'. mylist is now just 'a', 'c'

LINSERT {listname} // inserts item out of a list from the left (head)

RINSERT {listname} // inserts item out of a list from the right (tail)

SETS

Unordered collection of strings that ensures all items entries are unique. adding an item which already exxists will not add it.

SADD {setname} {Value} // adds an item to set

SADD countrycodes "PH"
SADD countrycodes "US"
SADD countrycodes "JP"

SISMEMBER {setname} {value} // validates if a member exists by responding 1 = true or 0= = false

SISMEMBER countrycodes "JP"
// returns 1 (integer)

SMEMBERS {setname} // retrieve the list of set items

SMEMBERS countrycodes 
// returns "PH", "US", "JP"

SCARD {setname} // retrieves the cardinality (number of elements) in a set

SCARD countrycodes
// returns 3 (integer)

SMOVE {setname-from} {setname-to} {value} // moves an element from a set to another

SMOVE countrycodes asiancountrycodes "PH"
SMOVE countrycodes asiancountrycodes "JP"
SMEMBERS countrycodes 
// returns only "US"

SREM {setname} {value} // removes a value from a set

SREM asiancountrycodes  "JP"

SORTED SETS

Much like sets but allows you to specify the z-order (index)

HASH

Creates a key value pair collection much like a JSON object (hashtable)

HSET {hashname} {key} {value} // sets value of a hash

HSET user:adonis fullname "Adonis Lee Villamor"
HSET user:adonis email "[email protected]"

HGET {hashname} {key} // retrieves the value of a key in hash table

HGET user:adonis fullname
// returns "Adonis Lee Villamor"

HGETALL {hashname} {key} // retrieves all the key and values in hash table

HGETALL user:adonis
// returns "fullname", "Adonis Lee Villamor", "email", "[email protected]"

HMSET {hashname} {{key} {value}} {...} // sets multiple keys and vaalues in the hash

HMSET user:saitomohito fullname "Sai Tomohito" email "[email protected]" age 49

HKEYS {hashname} and HVALS {hashnam} // retrieved only the keys or values