How to convert column heading to column values and its values in another column in postgresql

Question

I have a table like this say the table name is online-websites and the values it has is the number of times I used it.

Amazon	Flipkart	Myntra
5	4	3

I want to convert it to following format

Website name	Count
Amazon	5
Flipkart	4
Myntra	3.

How can I achieve this?

Thanks in Advance!

Answer 1

for your specific example one common way to unpivot is to lateral-join to a values-table construct:

select p.*
from t,
lateral (
  values
  ('Amazon', t.Amazon),
  ('Flipkart', t.Flipkart),
  ('Myntra', t.Myntra)
)p(SiteName, count)
order by count desc;