将我的列转换为 postgresql 中的行而不创建任何扩展

Question

I have a data result from a view like below,

But I want a view like this

Can any one help me to do this via postgresql without using extensions.

Answer 1

use aggregation

select project, max(case when role='owner' then name end) as owner,
 max(case when role='client' then name end) as client,
 max(case when role='Team' then name end) as Team
from table 
group by project;

Alternatively you can use the filter() clause which makes this a bit easier to read:

select project, 
       max(name) filter (where role='owner') as owner,
       max(name) filter (where role='client') as client,
       max(name) filter (where role='Team') as Team
from table 
group by project;