Pivoting Data in PostgresSQL

Question

I have a table as

Start Date	sequence No	Count	Emp_id
old	0	1	1
2020-12-07	1	15	1
More	2	4	1
Total	3	20	1
old	0	15	2
2020-12-07	1	20	2
More	2	5	2
Total	3	40	2

I require output as

Emp_id	Old	2020-12-07	More	Total
1	1	15	4	20
2	15	20	5	40

Can someone please give me some idea or point in a direction on how can i achieve the desired output?

Answer 1

For a fixed list of values, you can use conditional aggregation:

select emp_id
    max(count) filter(where start_date = 'old'       ) as val_old,
    max(count) filter(where start_date = '2020-12-07') as val_2020_12_07,
    max(count) filter(where start_date = 'More'      ) as val_more,
    max(count) filter(where start_date = 'Total'     ) as val_total
from mytable
group by emp_id