DENSE_RANK
Returns the rank of a value within a group of values, without gaps in the ranks.
The rank value starts at 1 and continues up sequentially.
If two values are the same, they have the same rank.
Analyze Syntax
func.dense_rank().over(partition_by=[<columns>], order_by=[<columns>])
Analyze Examples
table.department, func.sum(salary), func.dense_rank().over(order_by=func.sum(table.salary).desc()).alias('dense_rank')
| department | total_salary | dense_rank |
|------------|--------------|------------|
| IT | 172000 | 1 |
| HR | 160000 | 2 |
| Sales | 77000 | 3 |
SQL Syntax
DENSE_RANK() OVER ( [ PARTITION BY <expr1> ] ORDER BY <expr2> [ ASC | DESC ] [ <window_frame> ] )
SQL Examples
Create the table
CREATE TABLE employees (
employee_id INT,
first_name VARCHAR,
last_name VARCHAR,
department VARCHAR,
salary INT
);
Insert data
INSERT INTO employees (employee_id, first_name, last_name, department, salary) VALUES
(1, 'John', 'Doe', 'IT', 90000),
(2, 'Jane', 'Smith', 'HR', 85000),
(3, 'Mike', 'Johnson', 'IT', 82000),
(4, 'Sara', 'Williams', 'Sales', 77000),
(5, 'Tom', 'Brown', 'HR', 75000);
Calculating the total salary per department using DENSE_RANK
SELECT
department,
SUM(salary) AS total_salary,
DENSE_RANK() OVER (ORDER BY SUM(salary) DESC) AS dense_rank
FROM
employees
GROUP BY
department;
Result:
department | total_salary | dense_rank |
---|---|---|
IT | 172000 | 1 |
HR | 160000 | 2 |
Sales | 77000 | 3 |
Last modified June 11, 2024 at 7:47 PM EST: adding window functions (6bcb2f2)