sql query to count two type in single cloumn - 


buses ---------------- |bus_no     |bus_name |type |avail_seat

i have calculate how many ac , non ac buses there?

my query count is: 

count(*)bus_count sum(case when type='ac' 1 else 0) sum (case when type="non ac" 1 else 0) buses group bus_number;

assuming there 2 values in 'type' column, following query work: 

select type,  count (*) bus_count bus group 1;

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