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Table: Department
+---------------+---------+ | Column Name | Type | +---------------+---------+ | id | int | | revenue | int | | month | varchar | +---------------+---------+ (id, month) is the primary key of this table. The table has information about the revenue of each department per month. The month has values in ["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"].
Write an SQL query to reformat the table such that there is a department id column and a revenue column for each month.
The query result format is in the following example:
Department table: +------+---------+-------+ | id | revenue | month | +------+---------+-------+ | 1 | 8000 | Jan | | 2 | 9000 | Jan | | 3 | 10000 | Feb | | 1 | 7000 | Feb | | 1 | 6000 | Mar | +------+---------+-------+ Result table: +------+-------------+-------------+-------------+-----+-------------+ | id | Jan_Revenue | Feb_Revenue | Mar_Revenue | ... | Dec_Revenue | +------+-------------+-------------+-------------+-----+-------------+ | 1 | 8000 | 7000 | 6000 | ... | null | | 2 | 9000 | null | null | ... | null | | 3 | null | 10000 | null | ... | null | +------+-------------+-------------+-------------+-----+-------------+ Note that the result table has 13 columns (1 for the department id + 12 for the months).
Runtime: 308 ms
1 # Write your MySQL query statement below 2 select id, max(case when month = 'Jan' then revenue end) as Jan_Revenue, 3 max(case when month = 'Feb' then revenue end) as Feb_Revenue, 4 max(case when month = 'Mar' then revenue end) as Mar_Revenue, 5 max(case when month = 'Apr' then revenue end) as Apr_Revenue, 6 max(case when month = 'May' then revenue end) as May_Revenue, 7 max(case when month = 'Jun' then revenue end) as Jun_Revenue, 8 max(case when month = 'Jul' then revenue end) as Jul_Revenue, 9 max(case when month = 'Aug' then revenue end) as Aug_Revenue, 10 max(case when month = 'Sep' then revenue end) as Sep_Revenue, 11 max(case when month = 'Oct' then revenue end) as Oct_Revenue, 12 max(case when month = 'Nov' then revenue end) as Nov_Revenue, 13 max(case when month = 'Dec' then revenue end) as Dec_Revenue 14 15 from Department 16 group by id