SUM on different columns based on other columns values

Question

I bet title is not saying clearly what I am trying to achieve as complete newbie but will try to explain my problem below and hope some one will find a minute to share their wisdom :) Lets say we have a table called TYPES (Microsoft SQL Server) updated periodically ie every half hour. it consist of unique types, for each type there is number of offered transactions (if any) every update window (in reality it has millions of rows, hundreds of types and dozens of columns kept over a few years) But to keep it simple:

DateTime	Type	Offered
2021-11-04 09:00	Type1	300
2021-11-04 09:00	Type2	30
2021-11-04 09:00	Type3	255
2021-11-04 09:30	Type 1	244
2021-11-04 09:30	Type 2	118
2021-11-04 09:30	Type 3	90

I am trying to sum offered for a given day (24 hours period) for selected types (lets say type1 and type3) separately in one select if possible ie:

DateTime	Type1_sum	Type3_sum
2021-11-04	5621	4521
2021-11-05	5234	3651

Many thanks !

Answer 1

You can achieve this by grouping on the date portion of column [DateTime] then using conditional aggregation:

select
    cast([DateTime] as date) as [DateTime],
    sum(case [Type] when 'Type1' then [Offered] end) as Type1_sum,
    sum(case [Type] when 'Type3' then [Offered] end) as Type3_sum
from YourTable
group by cast([DateTime] as date)