Notes from “Redis Getting Started Guide.” Note: Which type to use depends on the specific situation. The following is just one approach.

Data Types

string String type (simplest key-value)

  SET bar 1
  GET bar

hash Hash type (key-field1-value1-field2-value2…)

  HSET car price 500
  HSET car name BMW
  HGET car name

list List type (key-value1-value2…)

  Linked list implementation. Fast access to data near both ends, but slower access to middle elements as the list grows.
  More suitable for "news feed" or "logs" where middle elements are rarely accessed.

  LPUSH numbers 1 2 3
  RPUSH numbers 6 5 4
  LPOP numbers
  RPOP numbers
  LRANGE numbers 0 -1

set Set type (key-member1-member2…)

  SADD letters a b c
  SREM letters c d
  SMEMBERS letters
  SISMEMBER letters a
  SDIFF lettersA lettersB
  SINTER lettersA lettersB
  SUNION lettersA lettersB

zset Sorted set type (key-score1-member1-score2-member2…)

  ZADD scoreboard 89 Tom 68 Peter 100 David
  ZSCORE scoreboard Tom
  ZRANGE scoreboard 0 -1
  ZRANGE scoreboard 60 90 WITHSCORES

Blog System Implementation

Blog name storage

  key = blog.name
  type = string
  e.g.
  SET blog.name
  GET blog.name

Post auto-increment ID

  key = posts:count
  type = string
  e.g.
  $postID = INCR posts:count

Post view count statistics

  key = post:$postID:page.view
  type = string
  e.g.
  $pageViewCount = INCR post:10:page.view

Post data (Method 1: Store data as JSON)

  key = post:$postID:data
  type = string
  e.g.
  $jsonData = jsonSerialize($title,$content,$author,$time)
  SET post:10:data $jsonData
  GET post:10:data $jsonData

Post data (Method 2: Hash)

  key = post:$postID
  type = hash
  e.g.
  HSET post:10 title hello
  HSET post:10 content helloworld
  HSET post:10 author everettjf
  HSET post:10 time Now()

Post slug

  key = slug.to.id
  type = hash
  e.g.
  $isSlugAvailable = HSETNX slug.to.id $newSlug 10

Store post IDs (Method 1: List)

  key = posts:list
  type = list
  e.g.
  Lists make pagination and post deletion convenient
  LPUSH posts:list 10
  $postsIDs = LRANGE posts:list,$start,$end
  for each $id in $postsIDs
    $post = HGETALL post:$id
    $title = $post.title

Store post IDs, sorted by time (Method 2: Sorted set)

  key = posts:createtime
  type = zset
  e.g.
  Sorted set stores post id and creation time (Unix time)
  ZREVRANGEBYSCORE can also get posts within a time range

Store comment list

  key = post:$postID:comments
  type = list
  e.g.
  $serializedComment = jsonSerialize($author,$email,$time,$content)
  LPUSH post:10:comments,$serializedComment

Store logs

  key = logs
  type = list
  e.g.
  LPUSH logs $serializedLog

Store tags

  All tags for a post are different, and there's no ordering requirement.
  key = post:$postID:tags
  type = set
  e.g.
  SADD post:10:tags cpp redis wechat php
  $tags = SMEMBERS post:10:tags

List all posts under one or more specified tags

  key = tag:$tagName:posts
  type = set
  e.g.
  post:1:tags -> java
  post:2:tags -> java , mysql
  tag:java:posts -> 1 , 2
  tag:mysql:posts -> 2

  $postsIDsBothWithTagJavaMysql = SINTER tag:java:posts tag:mysql:posts

Sort by view count

  key = posts:view
  type = zset
  e.g.
  ZINCRBY posts:page.view 1 $postID

  $postsIDs = ZREVRANGE posts:page.view $start $end
  for each $id in $postsIDs
    $postData = HGETALL post:$id