在只有一列作为查询基础的MySQL中如何做数据透视

Question

I saw a lot of ways on how to do pivot in MySQL but I can't relate it in my situation.

My situation is, I have a column called date_of_mem in tbl_members . I need to count how many member did register in that particular month and year.

For Example:

I have a table called tbl_members with column named id , fname , mname , lname and date_of_mem and so forth.

Now, I want to have this result:

Year | January | February | March | April | May | June | July ...
2013 | 100     | 250      | 50    | 60    | 300 | 280  | 125  ...
2014 | 101     | 240      | 20    | 40    | 200 | 180  | 145  ...

How to do this in MySQL.

Thanks in advance...

Answer 1

select      year(date_of_mem) as yr,
            sum(case when month(date_of_mem) = 1 then 1 else 0 end) as january,
            sum(case when month(date_of_mem) = 2 then 1 else 0 end) as february,
            sum(case when month(date_of_mem) = 3 then 1 else 0 end) as march,
            sum(case when month(date_of_mem) = 4 then 1 else 0 end) as april,
            sum(case when month(date_of_mem) = 5 then 1 else 0 end) as may,
            sum(case when month(date_of_mem) = 6 then 1 else 0 end) as june,
            sum(case when month(date_of_mem) = 7 then 1 else 0 end) as july,
            sum(case when month(date_of_mem) = 8 then 1 else 0 end) as august,
            sum(case when month(date_of_mem) = 9 then 1 else 0 end) as september,
            sum(case when month(date_of_mem) = 10 then 1 else 0 end) as october,
            sum(case when month(date_of_mem) = 11 then 1 else 0 end) as november,
            sum(case when month(date_of_mem) = 12 then 1 else 0 end) as december
from        tbl_members
group by    year(date_of_mem)