SQL
Identify and Count Duplicate Records in a SQL Table
Learn to find and count duplicate entries in your SQL database table using a simple GROUP BY and HAVING clause, essential for data cleansing and integrity checks.
SELECT column1, column2, COUNT(*) as duplicate_count
FROM your_table
GROUP BY column1, column2
HAVING COUNT(*) > 1;
How it works: This query groups rows by the combination of `column1` and `column2`. The `HAVING` clause then filters these groups to show only those where the count of rows is greater than 1, indicating that there are duplicate entries for that specific combination of values. This is crucial for identifying data quality issues.