Skip to main content
Key commands allow you to manage keys across all data types, handle expiration, and perform key-level operations.

​
DEL

Delete one or more keys. Syntax 
DEL key [key ...]
​
key
string
required
One or more keys to delete
Return value
​
count
integer
The number of keys that were removed
Examples 
redis-cli> SET key1 "Hello"
OK
redis-cli> SET key2 "World"
OK
redis-cli> DEL key1 key2 key3
(integer) 2
Time complexity: O(N) where N is the number of keys to remove

​
EXISTS

Check if one or more keys exist. Syntax 
EXISTS key [key ...]
​
key
string
required
One or more keys to check
Return value
​
count
integer
The number of keys that exist
Examples 
redis-cli> SET key1 "Hello"
OK
redis-cli> EXISTS key1
(integer) 1
redis-cli> EXISTS key1 key2
(integer) 1
redis-cli> EXISTS nosuchkey
(integer) 0
Time complexity: O(N) where N is the number of keys to check

​
EXPIRE

Set a key’s time to live in seconds. Syntax 
EXPIRE key seconds
​
key
string
required
The key to set expiration on
​
seconds
integer
required
The time to live in seconds
Return value
​
result
integer
1 if the timeout was set, 0 if the key does not exist
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> EXPIRE mykey 10
(integer) 1
redis-cli> TTL mykey
(integer) 10
Time complexity: O(1)

​
PEXPIRE

Set a key’s time to live in milliseconds. Syntax 
PEXPIRE key milliseconds
​
key
string
required
The key to set expiration on
​
milliseconds
integer
required
The time to live in milliseconds
Return value
​
result
integer
1 if the timeout was set, 0 if the key does not exist
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> PEXPIRE mykey 1500
(integer) 1
redis-cli> PTTL mykey
(integer) 1499
Time complexity: O(1)

​
EXPIREAT

Set the expiration for a key as a Unix timestamp (seconds). Syntax 
EXPIREAT key timestamp
​
key
string
required
The key to set expiration on
​
timestamp
integer
required
Unix timestamp in seconds
Return value
​
result
integer
1 if the timeout was set, 0 if the key does not exist
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> EXPIREAT mykey 1735689600
(integer) 1
Time complexity: O(1)

​
PEXPIREAT

Set the expiration for a key as a Unix timestamp (milliseconds). Syntax 
PEXPIREAT key timestamp_ms
​
key
string
required
The key to set expiration on
​
timestamp_ms
integer
required
Unix timestamp in milliseconds
Return value
​
result
integer
1 if the timeout was set, 0 if the key does not exist
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> PEXPIREAT mykey 1735689600000
(integer) 1
Time complexity: O(1)

​
PERSIST

Remove the expiration from a key. Syntax 
PERSIST key
​
key
string
required
The key to persist
Return value
​
result
integer
1 if the timeout was removed, 0 if the key does not exist or does not have an expiration
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> EXPIRE mykey 10
(integer) 1
redis-cli> TTL mykey
(integer) 10
redis-cli> PERSIST mykey
(integer) 1
redis-cli> TTL mykey
(integer) -1
Time complexity: O(1)

​
TTL

Get the time to live for a key in seconds. Syntax 
TTL key
​
key
string
required
The key to check
Return value
​
ttl
integer
TTL in seconds, -1 if the key exists but has no expiration, -2 if the key does not exist
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> EXPIRE mykey 10
(integer) 1
redis-cli> TTL mykey
(integer) 10
Time complexity: O(1)

​
PTTL

Get the time to live for a key in milliseconds. Syntax 
PTTL key
​
key
string
required
The key to check
Return value
​
ttl
integer
TTL in milliseconds, -1 if the key exists but has no expiration, -2 if the key does not exist
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> PEXPIRE mykey 1500
(integer) 1
redis-cli> PTTL mykey
(integer) 1499
Time complexity: O(1)

​
TYPE

Determine the type stored at a key. Syntax 
TYPE key
​
key
string
required
The key to inspect
Return value
​
type
string
Type of the key: string, list, set, hash, zset, or none if the key does not exist
Examples 
redis-cli> SET key1 "value"
OK
redis-cli> LPUSH key2 "a"
(integer) 1
redis-cli> SADD key3 "a"
(integer) 1
redis-cli> TYPE key1
string
redis-cli> TYPE key2
list
redis-cli> TYPE key3
set
Time complexity: O(1)

​
KEYS

Find all keys matching a glob pattern. Syntax 
KEYS pattern
​
pattern
string
required
Glob-style pattern (* matches any, ? matches one character, […] matches character set)
Return value
​
keys
array
List of keys matching the pattern
Examples 
redis-cli> MSET firstname Jack lastname Stuntman age 35
OK
redis-cli> KEYS *name*
1) "firstname"
2) "lastname"
redis-cli> KEYS a??
1) "age"
redis-cli> KEYS *
1) "firstname"
2) "lastname"
3) "age"
Time complexity: O(N) where N is the number of keys in the database Warning: Use KEYS only in development. For production, use SCAN.

​
SCAN

Incrementally iterate over keys. Syntax 
SCAN cursor [MATCH pattern] [COUNT count]
​
cursor
integer
required
The cursor position (use 0 to start a new iteration)
​
MATCH
string
Glob pattern to filter keys
​
COUNT
integer
Hint for how many keys to return per iteration (default: 10)
Return value
​
result
array
Array with two elements: [0] next cursor (0 when iteration is complete), [1] array of keys
Examples 
redis-cli> SCAN 0
1) "17"
2)  1) "key:12"
    2) "key:8"
    3) "key:4"
redis-cli> SCAN 17
1) "0"
2)  1) "key:14"
    2) "key:16"
redis-cli> SCAN 0 MATCH key:1* COUNT 100
1) "0"
2)  1) "key:12"
    2) "key:14"
    3) "key:16"
Time complexity: O(1) for every call, O(N) for a complete iteration

​
DBSIZE

Return the number of keys in the current database. Syntax 
DBSIZE
Return value
​
size
integer
The number of keys
Examples 
redis-cli> MSET key1 "a" key2 "b" key3 "c"
OK
redis-cli> DBSIZE
(integer) 3
Time complexity: O(1)

​
FLUSHDB

Delete all keys in the current database. Syntax 
FLUSHDB
Return value
​
result
string
Always returns OK
Examples 
redis-cli> SET key1 "Hello"
OK
redis-cli> SET key2 "World"
OK
redis-cli> FLUSHDB
OK
redis-cli> DBSIZE
(integer) 0
Time complexity: O(N) where N is the number of keys in the database

​
RENAME

Rename a key. Syntax 
RENAME key newkey
​
key
string
required
The key to rename
​
newkey
string
required
The new name for the key
Return value
​
result
string
OK on success, error if the source key does not exist
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> RENAME mykey mynewkey
OK
redis-cli> GET mynewkey
"Hello"
Time complexity: O(1)

​
RENAMENX

Rename a key only if the new key does not exist. Syntax 
RENAMENX key newkey
​
key
string
required
The key to rename
​
newkey
string
required
The new name for the key
Return value
​
result
integer
1 if the key was renamed, 0 if the new key already exists
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> SET myotherkey "World"
OK
redis-cli> RENAMENX mykey myotherkey
(integer) 0
redis-cli> RENAMENX mykey mynewkey
(integer) 1
Time complexity: O(1)
Delete one or more keys asynchronously. Syntax 
UNLINK key [key ...]
​
key
string
required
One or more keys to delete
Return value
​
count
integer
The number of keys that were unlinked
Examples 
redis-cli> SET key1 "Hello"
OK
redis-cli> SET key2 "World"
OK
redis-cli> UNLINK key1 key2 key3
(integer) 2
Time complexity: O(1) for each key, O(N) overall where N is the number of keys Note: UNLINK is similar to DEL but performs the actual memory reclamation asynchronously.

​
COPY

Copy a key to another key. Syntax 
COPY source destination [REPLACE]
​
source
string
required
The source key
​
destination
string
required
The destination key
​
REPLACE
flag
Overwrite the destination key if it exists
Return value
​
result
integer
1 if the key was copied, 0 otherwise
Examples 
redis-cli> SET mykey "Hello"
OK
redis-cli> COPY mykey mynewkey
(integer) 1
redis-cli> GET mynewkey
"Hello"
Time complexity: O(N) where N is the size of the value

​
RANDOMKEY

Return a random key from the keyspace. Syntax 
RANDOMKEY
Return value
​
key
string | null
A random key, or null if the database is empty
Examples 
redis-cli> MSET key1 "a" key2 "b" key3 "c"
OK
redis-cli> RANDOMKEY
"key2"
redis-cli> RANDOMKEY
"key1"
Time complexity: O(1)

​
TOUCH

Alter the last access time of one or more keys. Syntax 
TOUCH key [key ...]
​
key
string
required
One or more keys to touch
Return value
​
count
integer
The number of keys that were touched
Examples 
redis-cli> SET key1 "Hello"
OK
redis-cli> SET key2 "World"
OK
redis-cli> TOUCH key1 key2
(integer) 2
Time complexity: O(N) where N is the number of keys

​
Redis Compatibility

Kora implements all standard Redis key management commands with identical semantics.

Build docs developers (and LLMs) love

Get started for freeTalk to us