jkasaudhan

Database	Origin Country	Details
ClickHouse	Russia	Developed by Yandex, open-sourced in 2016. Community-driven since.
Greenplum	USA	Originally open-source; closed in 2024 by VMware/Broadcom.
Apache Druid	USA	Built by Imply Data (Khosla Ventures-backed). Strong real-time analytics focus.
DuckDB	Netherlands	Lightweight engine with academic roots. Strong GitHub community.
StarRocks	China / USA	Developed by CelerData. Open-sourced under the Linux Foundation.

jkasaudhan

Criteria	ClickHouse	Greenplum	Apache Druid	DuckDB	StarRocks
Columnar Storage	✅	✅	✅	✅	✅
Open Source	✅ (Apache 2.0)	❌ (Closed Source)	✅	✅	✅ (Linux Foundation Project)
On-Premise Hosting	✅	✅	✅	✅	✅
Security & RBAC	✅	✅	✅	✅	✅
Tool Integration (Airbyte, Metabase)

jkasaudhan

// Transforms array or any iterables of [key, value] pairs into object
const entries = [['name', 'JK'], ['age', '30']];
Object.fromEntries(entries);
// {name: "JK", age: "30"}

jkasaudhan

// Filter out successfull i.e fulfilled or resolved promises
const promises = [ fetch('index.html'), fetch('https://does-not-exist/') ];
const results = await Promise.allSettled(promises);
const successfulPromises = results.filter(p => p.status === 'fulfilled');

// Filter out failed promises
const promises = [ fetch('index.html'), fetch('https://does-not-exist/') ];

const results = await Promise.allSettled(promises);
const errors = results.filter(p => p.status === 'rejected')

jkasaudhan

// English version
const formatter = new Intl.ListFormat('en');

formatter.format(['january', 'february', 'march'])
// january, february, and march

const formatterConj = new Intl.ListFormat('en', {type: 'conjunction'});
// january, february, and march => by defaut type is 'conjunction'

const formatterDisj = new Intl.ListFormat('en', {type: 'disjunction'});

jkasaudhan

// For english version - it can be applied to second, minute,
// day, week, hour, month and quarter
const rtf = new Intl.RelativeTimeFormat('en');

rtf.format(2, 'day')
// in 2 days

rtf.format(-2, 'day')
// two days ago

jkasaudhan

// Without .flatMap()
var arr1 = [1, 2, 3, 4];

arr1.map(x => [x * 2]); 
// [[2], [4], [6], [8]]

arr1.map(x => [x * 2]).flat();
// [2,4,6,8]

// With .flatMap() => it is faster than above method

jkasaudhan

<img src="teaser.jpg" loading="lazy" alt="…" /> 
<iframe src="youtube.html" loading="lazy"></iframe>

jkasaudhan

class Person {
  #salary = '12345'; // => private class field
  
  getSalary() {
  this.#salary;
  }
}
class jack = new Person();
console.log(jack.#salary); // will prompt syntax error as it is private filed

jkasaudhan

var arr1 = [[1,2], [3,4], [5, 6]];
arr1.flat();
// [1,2,3,4,5,6]

var arr2 = [1, 2, [3, 4]];
arr2.flat(); 
// [1, 2, 3, 4] 

var arr3 = [1, 2, [3, 4, [5, 6]]];
arr3.flat();