使用 Presto 旋转 SQL

Question

I have a set of records showing the status of implementation of software components. Each row has a feature area, a feature within that area, the product where that feature appears, and its implementation status (green, red, or yellow), like this:

Feature_Area	Feature	Product	Status
User experience	Sign Up	App1	Green
User experience	Sign Up	App2	Red
User experience	Log off	App1	Green
User experience	Log off	App2	Red
Back End	Update User	App3	Green
Back End	Delete User	App3	Red

I'd like to pivot this as shown here:

Specifically, I'd like:

1. A single row for each feature and columns for each app to show the status of that feature
2. Don't repeat the same feature area value over and over in the first column

I tried using the below, which got me a column for each app. I couldn't figure out how to group properly with this to get the output I was looking for. I'd welcome any ideas.

case when Product = 'App1' then title end as App1,
case when Product = 'App2' then title end as App2,
case when Product = 'App3' then title end as App3

Answer 1

Based on provided description I suggest to group by feature_area and feature and select arbitrary value in group (or maybe array_agg if you anticipate different ones) (note, I used Presto/Trino specificif for concise syntax instead of case ):

-- sample data
with dataset(Feature_Area, Feature, Product, Status) as (
    values ('User experience', 'Sign Up', 'App1', 'Green'),
        ('User experience', 'Sign Up', 'App2', 'Red'),
        ('User experience', 'Log off', 'App1', 'Green'),
        ('User experience', 'Log off', 'App2', 'Red'),
        ('Back End', 'Update User', 'App3', 'Green'),
        ('Back End', 'Delete User', 'App3', 'Red')
)

-- query
select Feature_Area,
       Feature,
       arbitrary(if(Product = 'App1', Status)) App1,
       arbitrary(if(Product = 'App2', Status)) App2,
       arbitrary(if(Product = 'App3', Status)) App3
from dataset
group by Feature_Area, Feature
order by Feature_Area desc, Feature desc;

Output:

Feature_Area	Feature	App1	App2	App3
User experience	Sign Up	Green	Red	NULL
User experience	Log off	Green	Red	NULL
Back End	Update User	NULL	NULL	Green
Back End	Delete User	NULL	NULL	Red