Resolved: please i need an aswer

Hi Mustafa!

This is a task you will need to solve frequently. Here's how to do it in different cases:

1. Finding duplicates in a single column:

Suppose you have a table students and you want to find duplicate student names:

SELECT name, COUNT(name) AS CountOf
FROM students
GROUP BY name
HAVING COUNT(name) > 1;

2. Finding duplicates across multiple columns

Suppose you want to find duplicates based on the name and age columns in the students table:

SELECT name, age, COUNT(*) AS CountOf
FROM students
GROUP BY name, age
HAVING COUNT(*) > 1;

thanks so much. that so helpful