$devvkit resources --cheatsheet redis-cheatsheet

Redis Cheatsheet

[databases]

Redis data types, commands, expiration, pub/sub, and performance patterns.

Redis is an in-memory data structure store used as a cache, message broker, and database. It supports rich data types: strings, hashes, lists, sets, sorted sets, and more — all accessed with atomic commands.

This cheatsheet covers the most useful commands for each data type, plus expiration, transactions, and pub/sub. Commands use the redis-cli syntax.

Strings

$SET key value

Set a string value.Example: SET user:1:name "Alice"

$GET key

Get a string value.Example: GET user:1:name // returns "Alice"

$INCR key

Atomically increment a number by 1. Creates key if not exists.Example: INCR page:visits // 1, 2, 3...

$INCRBY key n / DECRBY key n

Increment or decrement by a specific amount.Example: INCRBY cart:123:count 5

$SETEX key seconds value

Set a string value with a TTL (time-to-live) in seconds.Example: SETEX session:token 3600 "abc123"

$MSET key1 val1 key2 val2

Set multiple string keys atomically.Example: MSET user:1:name "Alice" user:1:age "30"

Hashes

$HSET key field value

Set a field in a hash.Example: HSET user:1 name "Alice" age 30

$HGET key field

Get a single field from a hash.Example: HGET user:1 name // returns "Alice"

$HGETALL key

Get all fields and values of a hash.Example: HGETALL user:1 // returns name, age, etc.

$HMSET key field1 val1 field2 val2

Set multiple hash fields. Superseded by HSET with multiple pairs.Example: HSET user:1 name "Alice" age 30 email "alice@x.com"

$HDEL key field [field ...]

Delete one or more hash fields.Example: HDEL user:1 temporary_field

Lists

$LPUSH key value

Prepend a value to a list (left side).Example: LPUSH queue job:1

$RPUSH key value

Append a value to a list (right side).Example: RPUSH queue job:2

$LPOP key / RPOP key

Remove and return the first/last element of a list.Example: LPOP queue // returns job:1

$LRANGE key start stop

Get a range of elements from a list. 0 is first, -1 is last.Example: LRANGE queue 0 -1 // entire list

$LLEN key

Get the length of a list.Example: LLEN queue

Sets & Sorted Sets

$SADD key member

Add a member to a set. Duplicates are ignored.Example: SADD tags:1 "javascript" "react"

$SMEMBERS key

Return all members of a set.Example: SMEMBERS tags:1

$SISMEMBER key member

Check if a value is a member of a set. Returns 0 or 1.Example: SISMEMBER tags:1 "rust"

$SINTER key1 key2

Return the intersection of multiple sets.Example: SINTER tags:1 tags:2 // common tags

$ZADD key score member

Add a member to a sorted set with a numeric score.Example: ZADD leaderboard 100 "Alice"

$ZRANGE key start stop [WITHSCORES]

Return members in a score range (low to high).Example: ZRANGE leaderboard 0 9 WITHSCORES // top 10

$ZREVRANGE key start stop [WITHSCORES]

Return members in reverse score order (high to low).Example: ZREVRANGE leaderboard 0 9 // top 10 highest

Expiration & Keys

$EXPIRE key seconds

Set a TTL on an existing key.Example: EXPIRE session:token 900 // 15 minutes

$TTL key

Get the remaining TTL in seconds. -1 means no expiry, -2 means key gone.Example: TTL session:token // returns 842

$DEL key [key ...]

Delete one or more keys.Example: DEL cache:page:home

$KEYS pattern

Find all keys matching a pattern. Use with caution in production (blocks Redis).Example: KEYS user:*

$SCAN cursor [MATCH pattern]

Cursor-based key iteration. Use instead of KEYS in production.Example: SCAN 0 MATCH session:* COUNT 100

Pub/Sub & Transactions

$PUBLISH channel message

Send a message to a channel. Subscribers receive it in real-time.Example: PUBLISH updates "New version deployed"

$SUBSCRIBE channel [channel ...]

Subscribe to one or more channels and listen for messages.Example: SUBSCRIBE updates

$MULTI / EXEC

Start a transaction block. All commands between MULTI and EXEC run atomically.Example: MULTI INCR views:1 INCR views:total EXEC

Redis Cheatsheet

Redis data types, commands, expiration, pub/sub, and performance patterns.

This cheatsheet covers the most useful commands for each data type, plus expiration, transactions, and pub/sub. Commands use the redis-cli syntax.

Strings

SET key value — Set a string value.

Example: SET user:1:name "Alice"

GET key — Get a string value.

Example: GET user:1:name // returns "Alice"

INCR key — Atomically increment a number by 1. Creates key if not exists.

Example: INCR page:visits // 1, 2, 3...

INCRBY key n / DECRBY key n — Increment or decrement by a specific amount.

Example: INCRBY cart:123:count 5

SETEX key seconds value — Set a string value with a TTL (time-to-live) in seconds.

Example: SETEX session:token 3600 "abc123"

MSET key1 val1 key2 val2 — Set multiple string keys atomically.

Example: MSET user:1:name "Alice" user:1:age "30"

Hashes

HSET key field value — Set a field in a hash.

Example: HSET user:1 name "Alice" age 30

HGET key field — Get a single field from a hash.

Example: HGET user:1 name // returns "Alice"

HGETALL key — Get all fields and values of a hash.

Example: HGETALL user:1 // returns name, age, etc.

HMSET key field1 val1 field2 val2 — Set multiple hash fields. Superseded by HSET with multiple pairs.

Example: HSET user:1 name "Alice" age 30 email "alice@x.com"

HDEL key field [field ...] — Delete one or more hash fields.

Example: HDEL user:1 temporary_field

Lists

LPUSH key value — Prepend a value to a list (left side).

Example: LPUSH queue job:1

RPUSH key value — Append a value to a list (right side).

Example: RPUSH queue job:2

LPOP key / RPOP key — Remove and return the first/last element of a list.

Example: LPOP queue // returns job:1

LRANGE key start stop — Get a range of elements from a list. 0 is first, -1 is last.

Example: LRANGE queue 0 -1 // entire list

LLEN key — Get the length of a list.

Example: LLEN queue

Sets & Sorted Sets

SADD key member — Add a member to a set. Duplicates are ignored.

Example: SADD tags:1 "javascript" "react"

SMEMBERS key — Return all members of a set.

Example: SMEMBERS tags:1

SISMEMBER key member — Check if a value is a member of a set. Returns 0 or 1.

Example: SISMEMBER tags:1 "rust"

SINTER key1 key2 — Return the intersection of multiple sets.

Example: SINTER tags:1 tags:2 // common tags

ZADD key score member — Add a member to a sorted set with a numeric score.

Example: ZADD leaderboard 100 "Alice"

ZRANGE key start stop [WITHSCORES] — Return members in a score range (low to high).

Example: ZRANGE leaderboard 0 9 WITHSCORES // top 10

ZREVRANGE key start stop [WITHSCORES] — Return members in reverse score order (high to low).

Example: ZREVRANGE leaderboard 0 9 // top 10 highest

Expiration & Keys

EXPIRE key seconds — Set a TTL on an existing key.

Example: EXPIRE session:token 900 // 15 minutes

TTL key — Get the remaining TTL in seconds. -1 means no expiry, -2 means key gone.

Example: TTL session:token // returns 842

DEL key [key ...] — Delete one or more keys.

Example: DEL cache:page:home

KEYS pattern — Find all keys matching a pattern. Use with caution in production (blocks Redis).

Example: KEYS user:*

SCAN cursor [MATCH pattern] — Cursor-based key iteration. Use instead of KEYS in production.

Example: SCAN 0 MATCH session:* COUNT 100

Pub/Sub & Transactions

PUBLISH channel message — Send a message to a channel. Subscribers receive it in real-time.

Example: PUBLISH updates "New version deployed"

SUBSCRIBE channel [channel ...] — Subscribe to one or more channels and listen for messages.

Example: SUBSCRIBE updates

MULTI / EXEC — Start a transaction block. All commands between MULTI and EXEC run atomically.

Example: MULTI INCR views:1 INCR views:total EXEC