Question

我必须生成一份报告，显示不同地点的名称以及在这些地点提供独特课程的次数。报告只需要指明城市和否。独特的课程产品，并按最多的独特产品排序。我遇到的问题是产品表有一个复合主键（提供开始日期和课程代码）

我运行此SQL查询，但由于您无法计算多个列，因此会出现错误。但我不确定如何分数。

SELECT 
    offlocation AS city, COUNT(distinct offbegindate,crscode) as no. of unique course offerings
FROM
    offering
GROUP BY offlocation
ORDER BY COUNT(distinct offbegindate,crscode) as no. of unique course offerings DESC;

非常感谢任何帮助。

Answer 1

只需进行微调，“行类型”计数不同：

SELECT 
    offlocation AS city,
    COUNT(distinct (offbegindate,crscode)) as no_of_unique_course_offerings
FROM
    offering
GROUP BY offlocation
ORDER BY no_of_unique_course_offerings DESC;

Answer 2

您可以尝试连接值：

SELECT 
    offlocation AS city, COUNT(distinct offbegindate || '-' || crscode) as no. of unique course offerings
FROM
    offering
GROUP BY offlocation
ORDER BY COUNT(distinct offbegindate,crscode) as no. of unique course offerings DESC;

Answer 3

希望这会奏效：

if (number % 3 == 0)
    if (number % 5 == 0)
        console.log("FizzBuzz");
    else
        console.log("Fizz");
else
    if (number % 5 == 0)
        console.log("Buzz");
    else
        console.log(numer);

Answer 4

选择计数（不同的CONCAT（offbegindate，'-'，crscode））来自cgtask.tsk_proj_cost;

需要使用复合主键计算不同的值

4 个答案: