AWS ATHENA 将列转置为多行

Question

I have a csv file uploaded to an S3 bucket which I pick up with AWS Glue then query using Athena. The CSV table is in the format below:

ID	Starting Time	Ending Time	Failure Sector	Recycling Rounds
1	5am/8am/1pm	6am/10am/3pm	/(5)/	0/0/
2	4am/6am/3pm/7pm	7am/8am/5pm/11pm	///(1)	1//1/

I want to convert that format into this:

ID	Starting Time	Ending Time	Failure Sector	Recycling Rounds
1	5am	6am	blank	0
1	8am	10am	(5)	0
1	1pm	3pm	blank	blank
2	4am	7am	blank	1
2	6am	8am	blank	blank
2	3pm	5pm	blank	1
2	7pm	11pm	(1)	blank

How do I accomplish that using SQL in Athena? Any help is appreciated. Thanks!

Answer 1

You can use split to transform varchar into array of varchars and then flatten with unnest which supports multiple arrays:

-- sample data
with dataset (ID, Starting_Time, Ending_Time, Failure_Sector, Recycling_Rounds) AS
         (VALUES (1, '5am/8am/1pm', '6am/10am/3pm', '/(5)/', '0/0/'),
                 (2, '4am/6am/3pm/7pm', '7am/8am/5pm/11pm', '///(1)', '1//1/'))

-- query
select st, et, fs, rr
from dataset,
unnest (split(Starting_Time,'/'), split(Ending_Time,'/'), split(Failure_Sector,'/'), split(Recycling_Rounds,'/')) 
    as t(st, et, fs, rr);

Output:

st	et	fs	rr
5am	6am		0
8am	10am	(5)	0
1pm	3pm
4am	7am		1
6am	8am
3pm	5pm		1
7pm	11pm	(1)