MINUS in SQL

The MINUS operator is used to return all rows from the first SELECT statement that are not present in the second SELECT statement. It essentially performs a set difference operation between two result sets.

? Syntax:

SELECT column_list FROM table1MINUSSELECT column_list FROM table2;

? Example:

Suppose you have two tables:

• employees_2023

• employees_2024

You want to find employees who were in 2023 but not in 2024:

SELECT employee_id FROM employees_2023MINUSSELECT employee_id FROM employees_2024;

? Notes:

• MINUS is supported in Oracle and some other databases.

• Equivalent in SQL Server and MySQL is done using:

Using NOT IN:

SELECT employee_id FROM employees_2023WHERE employee_id NOT IN (    SELECT employee_id FROM employees_2024);

Using LEFT JOIN and WHERE NULL:

SELECT e1.employee_idFROM employees_2023 e1LEFT JOIN employees_2024 e2 ON e1.employee_id = e2.employee_idWHERE e2.employee_id IS NULL;

Let me know if you want examples for a specific SQL dialect or alternatives to MINUS!