Question

I have more than 1 rows in a table that belong to same ID.

I want to select row where more columns contain data .

eg.

My data looks like this

select * from my_table where id=1

PK   Id   Col1   Col2   Col3   Col4   Col5   Col6   Col7   Col8   Col9   Col10
101  1    NULL   NULL   NULL   XX     NULL   NULL   NULL   NULL   NULL   NULL
102  1    NULL   NULL   NULL   XX     YY     NULL   ZZ     NULL   NULL   NULL
103  1    NULL   AA     NULL   NULL   NULL   NULL   NULL   NULL   NULL   NULL
104  1    NULL   NULL   NULL   NULL   NULL   BB     NULL   NULL   NULL   NULL
105  1    NULL   NULL   NULL   NULL   NULL   NULL   NULL   CC     NULL   NULL

I want query which will give me Output like this for id=1 : –

PK   Id   Col1   Col2   Col3   Col4   Col5   Col6   Col7   Col8   Col9   Col10
102  1    NULL   NULL   NULL   XX     YY     NULL   ZZ     NULL   NULL   NULL

Answer 1

Where pk is your primary key…

select * 
from YourBadlyStructuredTable
where pk in (
    select top 1 pk from YourBadlyStructuredTable
    unpivot (col for z in (col1,col2,col3, ...))u
    where id=1
    group by pk
    order by COUNT(*) desc
)

If you can’t specify your column names…

select 
    top 1 
    HorribleTable.* 
from
(
    select
        xmldata.value('(/x2/@PK)[1]','int') as PK1,
        xmldata.value('(/x2/@Id)[1]','int') as ID1,
        xmldata.value('count(/x2/@*)','int') as cnt
        from
        (
    select      
        t.x.query('.') as xmldata               
    from
        (   select convert(xml,(select * from HorribleTable for xml raw('x2'))) as x1) v
            cross apply
        v.x1.nodes('/x2') t(x)
    ) v
) v
    inner join HorribleTable on v.PK1 = HorribleTable.pk
where ID1 = 1 
order by cnt desc