# GROUP BY Clause

The **GROUP BY** clause is used together with the SELECT statement to group the same data. You can group one or more columns, but the columns to be grouped must exist.

## **Syntax**

```plaintext
""SELECT 
{ * | [column, ...] }
[ FROM from_item [, ...] ]
[ WHERE condition ]
[ GROUP BY grouping_element [, ...] ]
[ ORDER BY {expression [ ASC | DESC ] }];
```

## **Parameter Description**

* **GROUP BY clause**
    
    Groups the query results based on the values of one or more columns. The query results with the same value are in the same group.
    
    The **GROUP BY** clause is placed after the **WHRER** clause and before the **ORDER BY** clause in the SELECT statement.
    

## **Examples**

The **customer\_t1** table contains duplicate values of **c\_first\_name**. The duplicate values of **c\_first\_name** are in the same group, and the sum of the values of **Amount** is calculated.

```plaintext
""openGauss=# SELECT c_first_name, sum(Amount)  FROM customer_t1 GROUP BY c_first_name;
 c_first_name | sum
--------------+------
 James        | 5000
 Grace        | 1000
 Local        | 3000
              |
 Joes         | 2200
 Lily         | 3000
(6 rows)
```

[Previous](https://docs.opengauss.org/en/docs/latest/docs/BriefTutorial/distinct.html)