SQL
Identify Duplicate Rows in a SQL Table
Find and list rows that have duplicate values for specific columns using SQL's GROUP BY and HAVING clauses, essential for data cleansing.
SELECT email, COUNT(email)
FROM users
GROUP BY email
HAVING COUNT(email) > 1;
How it works: This snippet identifies all email addresses that appear more than once in the `users` table. It groups the records by email and then uses the `HAVING` clause to filter for groups where the count of emails is greater than one, indicating the presence of duplicates for that specific column.