如何选择2个不同的列并计算其中一个列

Question

好的，我正在努力做到以下几点。我有一张表有问题和答案。我想弄清楚每个问题每个答案我有多少答案。

Question                     Answer
--------                     ------
What is your favorite color? Blue
What is your favorite color? Red
What is your favorite color? Blue
What is your age?            12
What is your age?            15

现在我想要的是输出结果（查询）：

What is your favorite color? Blue 2
What is your favorite color? Red 1
What is your age? 12 1
What is your age? 15 1

OR

What is your favorite color? 2 1
What is your age? 1 1

在最后一部分......我会根据查询知道这些值的含义。

Answer 1

SELECT t.Question,
       t.Answer,
       COUNT(*) AS 'Count'
FROM YourTable AS t
GROUP BY t.Question,
         t.Answer

Answer 2

第二个问题的答案涉及count(distinct)：

select t.Question, count(distinct t.Answer) as NumAnswers,
       count(*) as NumAnswered
from table t
group by t.Question;