Aggregating different rows in one column SQL Query - sql

Question

Sorry, I didn't come up with a good title for the question, so feel free to change it accordingly.
I may describe my question with a minimal example in MS SQL server 2012:
create table #tmp
(
RowID varchar(10),
SectionCode int,
SectionName varchar(10)
)
insert into #tmp values('Record1' , 1 , 'AB');
insert into #tmp values('Record1' , 2 , 'CD');
insert into #tmp values('Record1' , 3 , 'EF');
insert into #tmp values('Record2' , 1 , 'AB');
insert into #tmp values('Record2' , 4 , 'GH');
insert into #tmp values('Record2' , 5 , 'IJ');
insert into #tmp values('Record3' , 2 , 'CD');
insert into #tmp values('Record3' , 5 , 'IJ');
I am trying to create a one row per record result in which every section is a column and if there is a row associated with a section, the corresponding column value is increased. This is (not) what I want (the same record data on different rows)
select RowID,
case when SectionName = 'AB' then 1 else 0 end as [AB Section] ,
case when SectionName = 'CD' then 1 else 0 end as [CD Section] ,
case when SectionName = 'EF' then 1 else 0 end as [EF Section] ,
case when SectionName = 'GH' then 1 else 0 end as [GH Section] ,
case when SectionName = 'IJ' then 1 else 0 end as [IJ Section]
from #tmp
group by RowID , SectionName
which gives this output:
I need this:
Thanks in advance

Answer 1

You can use pivot for this as below and manipulate the values of sections however you want.
SELECT rowid
,CASE
WHEN ab IS NULL
THEN 0
ELSE 1
END AS ab
,CASE
WHEN cd IS NULL
THEN 0
ELSE 1
END AS cd
,CASE
WHEN ef IS NULL
THEN 0
ELSE 1
END AS ef
,CASE
WHEN gh IS NULL
THEN 0
ELSE 1
END AS gh
,CASE
WHEN ij IS NULL
THEN 0
ELSE 1
END AS ij
FROM (
SELECT *
FROM #tmp
PIVOT(MAX(Sectioncode) FOR Sectionname IN (
AB
,CD
,EF
,GH
,IJ
)) pvt
) tab
I think the result you shown is not correct for record id 2. ij of record id 2 should be 1.

Answer 2

I think you want this:
select RowID,
sum(case when SectionName = 'AB' then 1 else 0 end) as [AB Section] ,
sum(case when SectionName = 'CD' then 1 else 0 end) as [CD Section] ,
sum(case when SectionName = 'EF' then 1 else 0 end) as [EF Section] ,
sum(case when SectionName = 'GH' then 1 else 0 end) as [GH Section] ,
from #tmp
group by RowID;
That is, you need aggregation functions. And the group by should contain the columns that you want to define each row (i.e. only the RowId).