FIRST_VALUE

Learn how to use the FIRST_VALUE window function in PlaidCloud Lakehouse. Returns the first value from an ordered group of values. Includes syntax and examples.

Returns the first value from an ordered group of values.

Analyze Syntax

func.first_value(<expr>).over(partition_by=[<columns>], order_by=[<columns>])

Analyze Examples

table.employee_id, table.first_name, table.last_name, table.salary, func.first_value(table.first_name).over(order_by=table.salary.desc()).alias('highest_salary_first_name')

employee_id | first_name | last_name | salary  | highest_salary_first_name
------------+------------+-----------+---------+--------------------------
4           | Mary       | Williams  | 7000.00 | Mary
2           | Jane       | Smith     | 6000.00 | Mary
3           | David      | Johnson   | 5500.00 | Mary
1           | John       | Doe       | 5000.00 | Mary
5           | Michael    | Brown     | 4500.00 | Mary

SQL Syntax

FIRST_VALUE(expression) OVER ([PARTITION BY partition_expression] ORDER BY order_expression [window_frame])

For the syntax of window frame, see Window Frame Syntax.

SQL Examples

CREATE TABLE employees (
  employee_id INT,
  first_name VARCHAR(50),
  last_name VARCHAR(50),
  salary DECIMAL(10,2)
);

INSERT INTO employees (employee_id, first_name, last_name, salary)
VALUES
  (1, 'John', 'Doe', 5000.00),
  (2, 'Jane', 'Smith', 6000.00),
  (3, 'David', 'Johnson', 5500.00),
  (4, 'Mary', 'Williams', 7000.00),
  (5, 'Michael', 'Brown', 4500.00);

-- Use FIRST_VALUE to retrieve the first name of the employee with the highest salary
SELECT employee_id, first_name, last_name, salary,
       FIRST_VALUE(first_name) OVER (ORDER BY salary DESC) AS highest_salary_first_name
FROM employees;


employee_id | first_name | last_name | salary  | highest_salary_first_name
------------+------------+-----------+---------+--------------------------
4           | Mary       | Williams  | 7000.00 | Mary
2           | Jane       | Smith     | 6000.00 | Mary
3           | David      | Johnson   | 5500.00 | Mary
1           | John       | Doe       | 5000.00 | Mary
5           | Michael    | Brown     | 4500.00 | Mary