JOINING 2 tables and pass values Into a Third Table - sql-server-2008

Question

I have 2 tables namely ItemList table and ItemChara table, having this kind of structure:
wherein, Item_Num of Item Chara is a foreign key of Item List table. Now I'm trying to JOIN these tables. With a given like these.
How can I JOIN these tables with those values to form something Like this
I'm trying to find out what is the simplest way to achieve this. I limit the colors in table Item Chara at maximum of 2 colors per Item so it won't exceed 2 colors per item. I want to make another column like Color1 and Color2 to get each color in each item. If it happens that the item doesn't have a color to pair up with, it would just left blank, or null maybe.
Sorry but I'm not sure what to call the thing that I want to do but I know the output that I want to have, so the question title might be irrelevant. I'll change it as soon as I found out.

Answer 1

One way to do this is to use the row_number() window function:
select
i.item_num, i.item_name,
max(case when rn = 1 then ic.chara_color end) color1,
max(case when rn = 2 then ic.chara_color end) color2
from itemlist i
join (
select
item_num, chara_color,
rn = row_number() over (partition by item_num order by chara_num)
from itemchara
) ic on i.item_num = ic.item_num
group by i.item_num, item_name;

Answer 2

Below code will give u the required result.
select A.item_num,A.Item_name,
max(Color_1) AS Color_1,
max(Color_2) As Color_2
from (
select il.item_num,il.Item_name,
(case when ic.chara_num = 1 then ic.chara_color END) AS Color_1,
(case when ic.chara_num = 2 then ic.chara_color END) AS Color_2
from Item_List il inner join Item_Chara ic on il.Item_Num = ic.Item_Num
) A
group by item_num,Item_name
This code is not tested may be have some syntax erro which u need to check and sort it out. Let me know if still ur facing some issue.

Answer 3

Similar to other answers, but since I already made it I might post it anyway.
;with itemlist(itemId, itemName)
as
(
select 1,'Bag'
union ALL
select 2,'Pen'
union ALL
select 3,'Bike'
union ALL
select 4,'Shoes'
)
,itemchara(charaId, itemId, charaColor)
as
(
select 1, 1, 'Blue'
union all
select 2, 1, 'Red'
union all
select 3, 2, 'Black'
union all
select 4, 2, 'Blue'
union all
select 5, 3, 'Green'
union all
select 6, 4, 'Black'
)
,tmp
as
(
select i.itemName
,c.*
,row_number () over ( partition by c.itemId order by c.charaId ) as r
from itemlist i
join itemchara c
on i.itemId = c.itemId
)
select t1. itemId
,t1.itemName
,t1.charaColor
,t2.charaColor
from tmp t1
left join tmp t2
on t1.r+1 = t2.r
and t1.itemId = t2.itemId
where t1.r = 1