List distinct tuples in a table (SQL query) (10 ways)
Jun 26, 2012 · What are the different ways of listing distinct tuples in a table, the original question from GOLDMAN SACHS says to list 10 different ways one such way is using DISTINCT . Can …
How to make a tuple be unique in SQL table? - Stack Overflow
Nov 22, 2016 · CREATE TABLE friends ( id1 INT, id2 INT, min_id INT AS (LEAST (id1,id2)) VIRTUAL, max_id INT AS (GREATEST (id1,id2)) VIRTUAL, UNIQUE KEY (min_id,max_id) );
Differences between key, superkey, minimal superkey, candidate …
Mar 20, 2016 · Super Key: The set of attributes which can uniquely identify a tuple is known as Super Key. For Example, STUD_NO, (STUD_NO, STUD_NAME) etc. Adding zero or more …
Types of Keys in Relational Model (Candidate, Super, Primary, Alternate ...
Apr 4, 2025 · Keys help to uniquely identify records in a table, which prevents duplication and ensures data integrity. Keys also establish relationships between different tables, allowing for …
Unique Key in DBMS - GeeksforGeeks
Jun 13, 2024 · In this article, we are going to see about the unique keys in DBMS along with their implementation in the table. Let's start with the definition of a unique key. What is a Unique …
SQL | UNIQUE Constraint - GeeksforGeeks
Mar 7, 2025 · The SQL UNIQUE constraint is an essential tool for ensuring data integrity and consistency within a database. By enforcing uniqueness in specific columns or combinations …
Using Tuple Expressions - SQL Server | Microsoft Learn
Jan 31, 2024 · A tuple is made up of one member from every dimension that is contained within a cube. Therefore, a tuple uniquely identifies a single cell within the cube. Note. A tuple that …
What is a Candidate Key in SQL? - Database.Guide
Aug 27, 2024 · A candidate key is a minimal set of attributes (columns) that uniquely identify a tuple (row) in a relation (table). In other words, a candidate key is a combination of one or …
sql - how to select unique tuples from same table - Stack Overflow
Oct 13, 2014 · I want to find all pairs of diffrent students that are enrolled in two or more sections together from. enroll (sid*, grade, dname*, cno*, sectno*) where each section is uniquely …
Generating n-Tuples with SQL - SQLServerCentral
Jun 1, 2001 · Let’s now write a SQL query that generates Tuples for all n where we have unique strings we want to combine: UNION ALL SELECT 1 + n.n, t.strcol + ',' + n.Tuples. FROM @t t …