Redis

by

June 6, 2021

1:46 pm

37 Comments on Redis

Database

Redis Playground

https://try.redis.io/

Note: This try redis io is community version on web so few commands might not work. To use redis’s full power you can download and install on your local system

Redis is an in-memory data structure store, used as a distributed, in-memory key–value database, cache and message broker, with optional durability. Redis supports different kinds of abstract data structures, such as strings, lists, maps, sets, sorted sets, HyperLogLogs, bitmaps, streams, and spatial indices.

Installation

To install redis on windows download msi package from here
https://github.com/microsoftarchive/redis/releases/

For Linux Distr

sudo apt-get install redis-server

To install PHPRedis client use following command

sudo apt-get install php-redis
#for specific version
sudo apt-get install php7.4-redis

To verify redis installed in your system
Note: On windows you might need to add redis exe path in environment variables

redis-cli PING

To see all keys

KEYS *

DATATYPES

  • string
  • list
  • set
  • sorted set
  • hash
  1. String
    Syntax to set string value
SET key value [EX seconds] [PX milliseconds] [NX|XX]

To set only string value

SET keyname value

To check whether key exist or not

EXISTS keyname

Get key’s value

GET keyname

To delete any specific key

DEL keyname

To delete all keys

FLUSHALL

SET string with expiry

SET key value
EXPIRE key expiry-time-in-seconds
#shortcut
SET key value EX expiry-time-in-seconds

To check expiry time of any key

TTL key

SET string values using key:spaces
This is required when you want to set values related to one entity

SET key:space value

2. List or Stack

To set list use LPUSH

LPUSH key value1
LPUSH key value2
LPUSH key value3
OR
LPUSH key value1 value2 value3

To get length of list

LLEN key

To access any value of list you need to use LRANGE

LRANGE key from-index to-index

Use -1 in to-value to get all elements from list

LRANGE key 0 -1

To get specific index value
NOTE this will act like stack so LIFO algorithm will apply here i.e. index 0 will give you last inserted/pushed value

LINDEX key 0

LPUSH and RPUSH (left and right push)

LPUSH key value
RPUSH key value

LPOP and RPOP

LPOP key
RPOP key

Remove specific element from list

LREM key count value

3. Sets

Set is similar to list the main difference is it does not allow duplicate members
Order is not maintained in set

To add member in sets

SADD key value1 value2 value3

To view members of sets

SMEMBERS key

To remove member from sets

SREM key member

To get length of Sets

SCARD key

Compare Sets

SINTER set1 set2
SDIFF set1 set2
SUNION set1 set2

4. Sorted Sets

Sorted set are similar to sets the major difference is it stored members based on score i.e. sorted by score

ZADD key score member

To add multiple members

ZADD key rank1 member1 rank2 member2

To get count of sorted sets

ZCOUNT key

To See all members of sorted sets

ZRANGE key 0 -1

To get rank(index) of specific member

ZRANK key member

To get score of specific member

ZSCORE key member

To remove member from sorted sets

ZREM key member

5. Hashes

Hash is used to set field value pair it is similar to associative array

To set hash

HGET key field1 value1
HGET key field2 value2

To get field value

HGET key field

To get all field values

HGETALL key

To get length of hash key

HLEN key

To add field values at once

HMSET key field1 value1 field2 value2 field3 value3

To get values at once

HMGET key field1 field2 field2

To delete specific field from hash

HDEL key field1 field2

Assignment (set and get values of each type)

  1. Create string name age and city and set value in it
  2. Create List of fruits, weekdays, planets and set values in it
    Print length and values of list
  3. Create Sets of employees and managers
    Print length and values of Sets
  4. Create Hash record1, record2, record3 and add fields name age city in each hash
    Print length and values of each hash

Reference Links

37 Replies to “Redis”

  6. the best adult generator pornjourney nsfw create erotic videos, images, and virtual characters. flexible settings, high quality, instant results, and easy operation right in your browser. the best features for porn generation.

    Reply

  8. Hello .!
    I came across a 153 fantastic resource that I think you should check out.
    This resource is packed with a lot of useful information that you might find helpful.
    It has everything you could possibly need, so be sure to give it a visit!
    https://thinkofgames.com/the-2-most-iconic-video-games/

    And don’t neglect, folks, that one always can in the piece locate solutions for the most most complicated queries. We tried to explain all of the information in an most accessible method.

    Reply

  14. Нужен проектор? http://projector24.ru большой выбор моделей для дома, офиса и бизнеса. Проекторы для кино, презентаций и обучения, официальная гарантия, консультации специалистов, гарантия качества и удобные условия покупки.

    Reply

  19. Hello .!
    I came across a 153 interesting website that I think you should visit.
    This resource is packed with a lot of useful information that you might find insightful.
    It has everything you could possibly need, so be sure to give it a visit!
    https://www.apunkagames.website/popular-design-programs-create-online-store/

    And do not neglect, guys, — one at all times can inside this publication locate solutions for the most the very complicated questions. We tried to explain the complete data using the extremely accessible way.

    Reply

  23. online pokies australia 5 dollar deposit, instant withdrawal online casino australia conference on gambling and risk taking (Belle) online craps australia,
    or best casino sign up offers uk

    Reply

  30. best online slot usa, best new zealandn roulette strategy and poker
    tour australia, or united statesn casinos still accepting skrill

    my web site – is evansville casino open (Floy)

    Reply

  31. Лучшее казино up x официальный сайт играйте в слоты и live-казино без лишних сложностей. Простой вход, удобный интерфейс, стабильная платформа и широкий выбор игр для отдыха и развлечения.

    Reply

  33. Лучшее казино up x играйте в слоты и live-казино без лишних сложностей. Простой вход, удобный интерфейс, стабильная платформа и широкий выбор игр для отдыха и развлечения.

    Reply

  34. 10 free spins no deposit is gun lake casino open today – Franklyn –
    uk, casino paypal deposit usa and where can i play poker online for real money in australia, or australian poker tournaments

    Reply

  35. buy poker machine united kingdom, no deposit online casino united states and las vegas usa casino online no deposit bonus codes, or online pokies australia wheres the gold

    My homepage – european roulette wheel table (Brett)

    Reply

  37. online pokies canada real, best payout online casino united states
    and lucky lusae slot machine, or age to enter night owl casino – orion stars – Vivien, in united
    kingdom

    Reply

Leave a Reply to can your bank account be hacked by depositing a check Cancel reply

Your email address will not be published.