mysql - How can I write this SQL query? -


i wondering if on sql query. it´s test failed , wanted learn. i've spent lot of time on it, watched tutorials on sql still don't how written..

there 2 tables (flights, occupation_flights) flight information , task to: write query gives list of flights next 7 days, , shows flight, number of available seats, number of occupied seats , % of occupied seats.

flights:                     flight  id_company   date      origin   destination places 1003       d3      20/01/2006   madrid  londres       40 1007       af      20/01/2006   paris   malaga        12 1003       15      30/01/2006   madrid  londres       20 1007       af      30/01/2006   paris   malaga        17

(places show number of places offered on each flight)

occupation_flights: flight id_company   date    passenger   seat 1003    ib       20/01/2006 07345128h   01v 1003    ib       20/01/2006 1013456213  01p 1003    ib       20/01/2006 08124356c   02v 1003    ib       20/01/2006 57176355k   02p 1007    af       20/01/2006 27365138a    1003    ib       30/01/2006 734512811   01v 1003    ib       30/01/2006 1013456213  02v 1003    ib       30/01/2006 57176355k

(when seat empty, means person has not yet issued ticket). test data thought number of available seats should sum cases when passenger not empty per flight , date , extract places. started smth like: 

select  f.flight,  f.places - (select (case when of.passanger not null 1 else 0 end)       occupation_flights of group of.flight, of.date) available, f.places - (select (case when of.passanger null 1 else 0 end) occupation_flights of group of.flight, of.date) occupied, 100.0 * ((f.places - (select (case when of.passanger not null 1 else 0 end) occupation_flights of group of.flight, of.date)) / f.places %occupied flights f join occupation_flights of on f.flight=of.flight f.date between dateadd(dd,-7,getdate() ) , getdate()  group f.flight

but it's not finished, because don't understand how make him calculate in groups flight , date @ same time, because there flights same flight number going on different dates. don't have access tables, test on paper , show know how write sql queries. grateful insights! many in advance!

mysql conform: sqlfiddle

select f.flight,f.mydate,f.places - count(of.seat) available_seats,         count(of.seat) occupied,         count(of.seat)/f.places * 100 percentage_occupied flights f join occupation_flights of on f.flight = of.flight , f.mydate = of.mydate of.mydate between date_add(curdate(), interval -7 day)and curdate()  group f.flight, f.mydate

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