13 lines
773 B
MySQL
13 lines
773 B
MySQL
|
SELECT (SELECT COUNT(*)
|
||
|
|
FROM (SELECT F1.carrier,
|
||
|
|
(SELECT AVG(arr_delay)
|
||
|
|
FROM Flight_delays F2
|
||
|
|
WHERE F1.carrier=F2.carrier
|
||
|
|
GROUP BY F2.carrier
|
||
|
|
HAVING AVG(F1.arr_delay)>10) AS 'avg_delay'
|
||
|
|
FROM Flight_delays F1
|
||
|
|
GROUP BY F1.carrier) AS t
|
||
|
|
WHERE t.avg_delay IS NOT NULL) / CAST((SELECT COUNT(*)
|
||
|
|
FROM (SELECT COUNT(*) AS 'count'
|
||
|
|
FROM Flight_delays
|
||
|
|
GROUP BY carrier) AS T) AS FLOAT) AS 'part_of_cont_delays';
|