Redis is a type of database and it can be added to your production level application to make it more performant. I will cover the basics of Redis and show a real-world example of Redis. In this article, we'll discuss: What is Redis? Why the hype around Redis? When to use Redis? Redis Installation Basic Redis Commands Lists Sets Hashes Using Redis to make your website 30-40% faster Using Redis as a primary database So let's dive in. What is Redis? Redis is an in-memory database with sub-millisecond latency. Redis stands for mote ctionary ervice. What makes Redis so powerful is that it stores the data in the memory and not in the slower disks. Every data point in the database is a key-value pair. The value can be any of the following fields: Re Di S String - Hello World Bitmap - 0011001 Bitfield - {325}{655}{678} Hash - {a: "hello", b:'world} List - [ A > B > C ] Set - { A, B, C} Sorted set - {A: 1, B: 2, C: 3} Geo-spatial - {A:(52, 2, 3)} Hyperlog Stream Why the hype around Redis? Redis is so popular because of its speed. Unlike a relational database where the data is stored in slower hard disks, Redis stores the data in RAM. Due to the usage of RAM, Redis is volatile, meaning that when the system shuts down, your data is also lost. Hence, Redis is usually not used as a persistent database like MongoDb or PostgresSql and is instead used for caching. Nowadays it’s more powerful as I will discuss below. 🌟 Super Fast data access:  Redis takes milliseconds to access data as opposed to many hundreds of milliseconds using traditional methods. When should you use Redis? Redis is not a replacement for your database. Instead, it is built on top of your traditional database. Any data that needs to be accessed frequently can be stored in Redis. It is also helpful when the database query is long and takes a lot of time to execute. Redis Installation - Ubuntu from the official Ubuntu PPA $ sudo add-apt-repository ppa:redislabs/redis
$ sudo apt-get update
$ sudo apt-get install redis - Mac use homebrew brew update
brew install redis - use to install Redis on windows Windows WSL Basic Redis Commands Startup Commands -  To start Redis server use the command redis-server To use the Redis CLI open a new terminal and enter and to close it use command redis-cli quit Basic Commands - Setting a value SET name your-name - Get the above value GET name - Delete a key-value by DEL name - To check if a key exists EXISTS name - Get all keys KEYS * - Clear all the data flushall Expiration - Check how long a key has before being deleted automatically. if the result is it means (Time To Live) is not set and it wont expire. ttl key-name -1 ttl - Set a of 10 seconds. expire key-name 10 ttl - To set a while setting a key value pair. setex name 10 your-name ttl Lists Lists are useful when we want to implement a queue or stack. Like in case of a messenger app, where we cache some of the recent messages. - Push an item into the left of a list. lpush fruits apple - Push an item into the right of a list. rpush fruits mango - Get all the items from the list. The stands for the index at the end of the list. lrange fruits 0 -1 -1 - Removes the leftmost item in the list. LPOP fruits - Removes the rightmost item in the list. RPOP fruits Sets Sets are similar to lists.  What makes a Set different is that it will only store unique values. - To add item into a set. (note: if we try to add "read book" again it won't be added as it is a duplicate) SADD todo "read book" - Show all the items in the todo set. SMEMBERS todo -  To remove item from set. SREM todo "read book" Hashes Whereas s and s in Redis hold sequences of items, Redis es store a mapping of keys to values. LIST SET HASH - Here is the key and is the value. HSET person name John name John - This returns the value associated with the key name and in this case it returns . HGET person name John - Get all the info about person. HGETALL person - Remove the name property. HDEL person name - To check if the property exists. HEXISTS person name Using Redis to make your website 30-40% faster Install Redis npm i redis Start your Redis server redis-server Import the package and create an instance // Import redis package
const Redis = require('redis')

// Create redis client, in case ofer development only
const redisClient = Redis.createClient()
// Incase of production pass your production instance url and use the below line
const redisClient = Redis.createClient({ url: "your-production-url"}) use the above instance to do all the commands I mentioned above. for example - redisClient redisClient.setex('photos', 3600, JSON.stringyfy(some-value-to-store)) Before adding Redis Caching The code below takes about to fetch a data of size 900kB. 480ms app.get("/photos", async(req, res) => {
    const albumId = req.query.albumId
    const { data } = await axios.get(
        "https://jsonplaceholder.typicode.com/photos"
        { params: { albumId }}
    )
}) After adding Redis Caching The code below takes about in the first fetch and in the recurrent fetch it takes only . Now that is some serious performance gain. 480ms 37ms // Import redis package
const Redis = require('redis');

// Create redis client, in case ofer development only
const redisClient = Redis.createClient();
// Incase of production pass your production instance url and use the below line
const redisClient = Redis.createClient({ url: 'your-production-url' });

app.get('/photos', async (req, res) => {
  const albumId = req.query.albumId;
  redisClient.get('photos', async (error, photos) => {
    if (error) console.error(error);
    if (photos != null) {
      return res.json(JSON.parse(photos));
    } else {
      const { data } = await axios.get('https://jsonplaceholder.typicode.com/photos', {
        params: { albumId }
      });
      redisClient.setex('photos', 3600, JSON.stringyfy(data));
      res.json(data);
    }
  });
}); In the above example we first check if we have already cached photos in our Redis cache, In case it is cached, the cached value is returned, else the photos are fetched from the API. Using Redis as a primary Database Redis is by nature super fast and doesn't need additional caching layers, but a necessary requirement of a database is to model complex relationships. Don't worry, Redis got you covered. Redis can be used as a multi-model database. It supports a variety of database paradigms with the help of various modules. Some of the most popular Redis modules are: RediSearch - Full-Text search over Redis. RedisGraph - A graph database with a Cypher-based querying language using sparse adjacency matrices. RedisBloom - Scalable Bloom filters. RedisJson - A JSON data type for Redis. RedisAI - A Redis module for serving tensors and executing deep learning graphs. Neural-redis - Online trainable neural networks as Redis data types. RedisTimeSeries - Time-series data structure for redis. Check out all the modules in . You can play around with these modules in . redis.io/modules Redis Enterprise Cloud free tier Not in a hurry? Read these My favorite algorithm (and data structure): HyperLogLog What is a message broker? You might also like - https://milindsoorya.site/blog/tips-for-using-async-await-write-better-java-script

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What Is Redis and How Can It Make Your Website 30-40% Faster?

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