Based on CASE Pivot multiple rows into single row and multiple columns - sql

Question

Suppose there is a table
NAME Unit Date Time Type LOAD
A1Cu 2 2020-01-02 10:30 CU 0.1
A1Ta 5 2020-01-02 10:30 TA 0.3
A1Ch 6 2020-01-02 10:30 CH 0.2
B1Ch 4 2020-02-15 11:40 CH 0.52
B1Ta 8 2020-02-15 11:40 TA 0.83
C1Ta 5 2020-06-18 21:00 TA 0.11
Z1Ch 8 2020-08-08 15:30 CH 0.24
D1Ta 8 2020-06-18 01:30 TA 0.3
C1Cu 6 2020-06-18 21:00 CU 0.2
Then for same date and time merge multiple rows into single column by applying following logic
FOR NAME AND UNIT (Stop when one of the condition is met)
IF Type CU Then take NAME & UNIT
ELSE IF Type CH Then take NAME & UNIT
ELSE IF Type TA Then take NAME UNIT
For Load Put in respective column
The final Result should be like
NAME Unit Date Time TypeCULoad TypeCHLoad TypeTALoad
A1Cu 2 2020-01-02 10:30 0.1 0.2 0.3
B1Ch 4 2020-02-15 11:40 NULL 0.52 0.83
C1Cu 6 2020-06-18 21:00 0.2 NULL 0.11
Z1Ch 8 2020-08-08 15:30 NULL 0.24 Null
D1Ta 8 2020-06-18 01:30 NULL NULL 0.3
I have the partial solution but finding it hard to get Name and Load Logic right:
SELECT Date, Time,[TypeCULoad], [TypeCHLoad ],[TypeTALoad] FROM
(
SELECT
Date, Time, col, val FROM(
SELECT *, 'Type'+Type+'Load' as Col, Load as Val FROM TESTAIR
) t
) tt
PIVOT ( max(val) for Col in ([TypeCULoad], [TypeCULoad],[TypeCULoad]) ) AS pvt
Result
Date Time TypeCULoad TypeCHLoad TypeTALoad
2020-01-02 10:30 0.1 0.2 0.3
2020-02-15 11:40 NULL 0.52 0.83
2020-06-18 21:00 0.2 NULL 0.11
2020-08-08 15:30 NULL 0.24 Null
2020-06-18 01:30 NULL NULL 0.3
Need help on Name and Load?

Answer 1

First try to get the desired results before applying PIVOT
with cte as
(
SELECT name, unit, date, time, 'Type' + Type + 'Load' as Col, Load as Val, Type, LEFT(name, 2) xxx,
RANK() OVER(PARTITION BY LEFT(name, 2) ORDER BY CASE type WHEN 'CU' THEN 1 WHEN 'CH' THEN 2 ELSE 3 END) dd
FROM TESTAIR
)
select name, unit, Date, Time, [TypeCULoad], [TypeCHLoad ], [TypeTALoad] from
(
select b.name, b.unit, a.date, a.time, a.col, a.val
from cte a
join cte b on a.xxx = b.xxx and b.dd = 1
) f
PIVOT (max(val) for Col in ([TypeCULoad], [TypeCHLoad],[TypeTALoad]) ) AS pvt