Sql server query to find duplicates values from given column

To find duplicates in the name column from the TempTable1 table, you can use a SQL query that employs the COUNT() function along with GROUP BY and HAVING clauses. 

Here’s how you can do it:

SELECT name, COUNT(*) AS name_count

FROM [TempTable1]

GROUP BY name

HAVING COUNT(*) > 1;

Explanation:

1. SELECT statement:

   • SELECT name, COUNT(*) AS name_count: This selects the name column and counts how many times each name appears in the table. The COUNT(*) function counts all rows for each name.

2. GROUP BY clause:

   • GROUP BY name: Groups the result set by the name column. This means that the COUNT(*) function will count occurrences of each unique name.

3. HAVING clause:

• HAVING COUNT(*) > 1: Filters the groups to only include those where the count of name occurrences is greater than 1. This effectively filters out unique names and shows only those that appear more than once, indicating duplicates.

Result:

The query will return rows where the name column has duplicate values, along with the count of how many times each name appears. This allows you to identify and manage duplicates in your TempTable1 table.