假设我有下面的表：

CREATE TABLE sales(
                      id serial PRIMARY KEY,
                      sales_employee VARCHAR(50) NOT NULL,
                      fiscal_year INT NOT NULL,
                      sale DECIMAL(14,2) NOT NULL
);
INSERT INTO sales(sales_employee,fiscal_year,sale)
VALUES('Bob',2016,100),
      ('Bob',2017,150),
      ('Bob',2018,200),
      ('Alice',2016,150),
      ('Alice',2017,100),
      ('Alice',2018,200),
      ('John',2016,200),
      ('John',2017,150),
      ('John',2018,250);

如何我得到下面的结果：

2016 Bob 100
2016 Alice 150
2016 John 200
2017 Bob 250
2017 Alice 250
2017 John 350
2018 Bob 450
2018 Alice 450
2018 John 600

真实的样本中的员工人数和年数要多得多。