Question

I have a query such as this:

select a.id, a.color, a.shade from colors a where a.color = 'red'

which fetches

ID     | Color      | shade
-------|------------|---------
23     |red         | dark10
525    |red         | light-10

Question:

How can I find all records in table colors where there are multiple (two) occurrences of samecolor AND their corresponding shades are NOT identical

e.g. records like the following will not be considered

ID     | Color      | shade
-------|------------|---------
23     |green       | light-10
324    |green       | light-10

Answer 1

You can do this by utilizing a GROUP BY clause with a HAVING COUNT(*) = 1 condition:

declare @colors table (
    id int,
    color nvarchar(100),
    shade nvarchar(100)
)

insert into @colors
        select 23, 'red', 'dark10'
union all select 525, 'red', 'light-10'
union all select 23, 'green', 'light-10'
union all select 324, 'green', 'light-10'

select c.*
from @colors c
inner join (
    select color, shade
    from @colors 
    group by color, shade
    having COUNT(*) > 1
) x
    on x.color = c.color
    and x.shade <> c.shade