Learning Data Types in Redis

I was doing a project that used redis and I found the data types to be kinda confusing. So, I wrote a blog post about the data types of redis.

string

So this data type is pretty straightforward. You can store strings in redis. For example, like this:

redis.set("fruit", "apple")

The fruit will be the key while apple would be the value.

list

The list data type can store an ordered collection of strings. These are some features of the list data type:

• ordered: Redis lists are ordered by the sequence in which they are added
• duplication: lists can contain duplicate elements
• You can insert, remove, or range query a redis list

For example, I can set a value by specifying the index:

// assuming that there's already a key named "fruit"
redis.lset("fruit", 0, "apple")

set

Simply put, set is an unordered collection of unique strings. Here are some key features of the set data type:

• unordered: Redis sets are unordered
• unique (duplication X): Redis sets don't allow the storing of duplicated values. Adding an already-existing element to a Redis set will have no effect

Here's how I can add an element in a Redis set:

redis.sadd("fruit", "apple")
redis.sadd("fruit", "apple") // this won't have any effect

sorted set

Sorted sets are sets with the added feature of being sorted. We can also increment or decrement the score value:

redis.zadd("fruit", {incr: true}, {
	member: "apple",
	score: 1
})

Note that the score value get incremented depending on the score value!

hash

Hashes is where we can store object data. I was pretty familiar with this one:

  await redis.hset("fruit", {
    id: 1,
    name: "apple",
    likeCount: 20
  })

I'll add more when I dive deeper into Redis :D