laravel sum and crosstab - mysql

Question

hi i am trying to solve this problem from 2 days please help. I have a table like below. i am trying to get crosstab display
expenditures
id name
1 exp1
2 exp2
3 exp3
4 exp4
5 exp5
stations
id name
1 station1
2 station2
3 station3
4 station4
expenses
expenditure_id station_id year month expense
1 1 2015 1 10
1 2 2015 1 20
1 3 2015 1 15
1 4 2015 1 10
1 1 2015 2 20
1 1 2015 3 30
1 1 2015 4 40
2 1 2015 1 20
2 1 2015 2 10
2 1 2015 3 20
I am trying get result like this
for year 2015
expenditure station1 station2 station3 station4
exp1 100 20 15 0
exp2 50 0 0 0
where value of station1 station2 will be the sum of month expense

Answer 1

This is the mysql query as your requirement, use Laravel query builder to run this query as raw query, if you donot know how to run raw query in laravel let me know, in the mean while run the query in phpmyadmin/mysql client and see whether its give you the desired output .
SELECT y.expenditure,
MAX(CASE y.station WHEN 'station1' THEN y.totalexpense END) 'station1',
MAX(CASE y.station WHEN 'station2' THEN y.totalexpense END) 'station2',
MAX(CASE y.station WHEN 'station3' THEN y.totalexpense END) 'station3',
MAX(CASE y.station WHEN 'station4' THEN y.totalexpense END) 'station4'
FROM (
SELECT exp.name AS expenditure,st.name AS station,x.totalexpense
FROM expenditures AS exp
LEFT JOIN
(SELECT expenditure_id,station_id,SUM(expense) as totalexpense
FROM expenses
WHERE year = '2015'
GROUP by expenditure_id,station_id
)
AS x ON exp.id = x.expenditure_id
LEFT JOIN stations AS st ON x.station_id = st.id
) AS y
GROUP BY y.expenditure
I assume you have only 4 stations, if stations are unknown numbers then you can use a prepared statement and create this dynamically: