--- title: "#union articles | Hashnode" description: "Explore 11 articles tagged #union on Hashnode. Tutorials, guides, and how-tos from the community." url: "https://hashnode.com/tag/union" --- Tag # #union 11 posts · 0 followers [Ved Pandey](https://hashnode.com/@Ved-Pandey) · [Aug 20](https://hashnode.com/posts/masterclass-on-typescript/6a870db098220ab7c71d638c) ### [Masterclass on TypeScript](https://vedpandeydev.hashnode.dev/masterclass-on-typescript?utm_source=hashnode&utm_medium=feed) If JavaScript works, why was TypeScript created? Today we'll answer exactly that, and along the way we'll understand how types work, why interfaces and generics exist, and how a TypeScript project run 16 min read · [vedpandeydev.hashnode.dev](https://vedpandeydev.hashnode.dev/masterclass-on-typescript?utm_source=hashnode&utm_medium=feed) [Johnny Santamaria](https://hashnode.com/@jds64) · [Mar 28](https://hashnode.com/posts/improving-multipartitionkey-typing-in-dagster-a-deep-dive/69c736bd7cf270651084a3d6) ### [Improving MultiPartitionKey Typing in Dagster: A Deep Dive](https://johnny603-repocasestudies.hashnode.dev/improving-multipartitionkey-typing-in-dagster-a-deep-dive?utm_source=hashnode&utm_medium=feed) Enhancing Type Safety and Flexibility in Partitioned Data Pipelines 12 min read · [johnny603-repocasestudies.hashnode.dev](https://johnny603-repocasestudies.hashnode.dev/improving-multipartitionkey-typing-in-dagster-a-deep-dive?utm_source=hashnode&utm_medium=feed) [Ashifur Rahaman](https://hashnode.com/@ashif-arsb) · [Oct 16, 2025](https://hashnode.com/posts/advanced-sql-set-operations/68f0993f4f25d414606642e0) ### [Advanced SQL - Set Operations](https://sqlinsights.hashnode.dev/advanced-sql-set-operations?utm_source=hashnode&utm_medium=feed) SQL set operations combine the results of two or more SELECT statements into a single result set. These operators are similar to mathematical set theory concepts and are used to merge, find commonalities, or identify differences between data sets. Fo... 3 min read · [sqlinsights.hashnode.dev](https://sqlinsights.hashnode.dev/advanced-sql-set-operations?utm_source=hashnode&utm_medium=feed) [Chetan Datta](https://hashnode.com/@chetan77) · [Oct 12, 2025](https://hashnode.com/posts/disjoint-set/68eba488a9fe332bb096c1a5) ### [Disjoint Set - Data Structure](https://chetan77.hashnode.dev/disjoint-set?utm_source=hashnode&utm_medium=feed) Introduction A disjoint set is a data structure that helps determine if two nodes are part of the same component efficiently. While BFS or DFS can be used to check this, a disjoint set can perform the task in constant time. It is particularly useful ... 2 min read · [chetan77.hashnode.dev](https://chetan77.hashnode.dev/disjoint-set?utm_source=hashnode&utm_medium=feed) [DbVisualizer](https://hashnode.com/@dbvisualizer) · [Jul 24, 2025](https://hashnode.com/posts/sql-union-all-the-fastest-way-to-combine-result-sets/6881d9f8d3081c71fb48ced7) ### [SQL UNION ALL: The Fastest Way to Combine Result Sets](https://thetable.hashnode.dev/sql-union-all-the-fastest-way-to-combine-result-sets?utm_source=hashnode&utm_medium=feed) Understand SQL UNION ALL and how it preserves duplicates. Learn syntax, best practices, and how it differs from JOIN and UNION. 2 min read · [thetable.hashnode.dev](https://thetable.hashnode.dev/sql-union-all-the-fastest-way-to-combine-result-sets?utm_source=hashnode&utm_medium=feed) [DbVisualizer](https://hashnode.com/@dbvisualizer) · [Jul 20, 2025](https://hashnode.com/posts/sql-union-vs-union-all-merge-select-results-in-sql-like-a-pro/687d66edc25c9a0c9a59668f) ### [SQL UNION vs UNION ALL: Merge SELECT Results in SQL Like a Pro](https://thetable.hashnode.dev/sql-union-vs-union-all-merge-select-results-in-sql-like-a-pro?utm_source=hashnode&utm_medium=feed) Merge multiple SELECT queries with SQL UNION and UNION ALL. Learn syntax, differences, examples, and use cases. 2 min read · [thetable.hashnode.dev](https://thetable.hashnode.dev/sql-union-vs-union-all-merge-select-results-in-sql-like-a-pro?utm_source=hashnode&utm_medium=feed) [Steve Hatmaker Jr.](https://hashnode.com/@Stevehatmakerjr) · [Oct 29, 2024](https://hashnode.com/posts/understanding-sql-joins-a-simple-guide/6720489be65f2bfa765ad8a0) ### [Understanding SQL Joins: A Simple Guide](https://stevehatmakerjr.com/understanding-sql-joins-a-simple-guide?utm_source=hashnode&utm_medium=feed) Have you ever tried to combine pieces of information from different sources? Maybe you have a list of your friends and another list of their favorite games. You might want to see who likes which game. In databases, we use something called joins to co... 5 min read · [stevehatmakerjr.com](https://stevehatmakerjr.com/understanding-sql-joins-a-simple-guide?utm_source=hashnode&utm_medium=feed) [Jyotiprakash Mishra](https://hashnode.com/@jpmishra) · [Dec 19, 2023](https://hashnode.com/posts/unions-arent-always-scary/65813df1599fba48a9cebe70) ### [Unions aren't always scary!](https://blog.jyotiprakash.org/unions-arent-always-scary?utm_source=hashnode&utm_medium=feed) Unions in C are user-defined data types that allow different data members to share the same memory space. They are particularly useful when dealing with situations where different data members need to occupy the same memory space at different times, ... 1 min read · [blog.jyotiprakash.org](https://blog.jyotiprakash.org/unions-arent-always-scary?utm_source=hashnode&utm_medium=feed) [woodstock](https://hashnode.com/@woodstock229) · [Dec 9, 2023](https://hashnode.com/posts/algebraic-type/65f6e4684f9eed70c4d0b040) ### [대수 타입(Algebraic type)](https://woodstock.hashnode.dev/algebraic-type?utm_source=hashnode&utm_medium=feed) 대수 타입(Algebraic type) 대수 타입이란 여러개의 타입을 합성해서 만드는 타입을 말한다. 합집합(Union) 타입 let a: string | number | boolean; a = 1; a = "hello"; a = true; Union 타입으로 배열 타입 정의하기 let arr: (number | string | boolean)\[\] = \[1, "hello", true\]; Union 타입과 객체 타입 type Dog = ... 1 min read · [woodstock.hashnode.dev](https://woodstock.hashnode.dev/algebraic-type?utm_source=hashnode&utm_medium=feed) [Akhil Nanavati](https://hashnode.com/@AkhilNanavati) · [Aug 30, 2023](https://hashnode.com/posts/revolving-credit-lines-with-union/64ef1a1126376610c4a7cd41) ### [Revolving Credit Lines with Union](https://akhilnanavati.hashnode.dev/revolving-credit-lines-with-union?utm_source=hashnode&utm_medium=feed) In today's world, how do we make payments? What do we use to make payments? What do we do to take out loans? How do we repay loans? We are at the mercy of traditional banks and their systems for facilitating each one of these. But are they always saf... 4 min read · [akhilnanavati.hashnode.dev](https://akhilnanavati.hashnode.dev/revolving-credit-lines-with-union?utm_source=hashnode&utm_medium=feed)