题解 | SQL274 考试分数(四)

WITH t1 AS (
    SELECT
        job,
        COUNT(job) AS num
    FROM grade
    GROUP BY job
),
t2 AS (
    SELECT 
        job,
        FLOOR((num + 1) / 2) AS start,
        CEIL((num + 1) / 2) AS end
    FROM t1
    ORDER BY job ASC
)
SELECT * FROM t2;