SQL从两个表中选择

Question

My first table is as below (not important):

tbl_Item

ItemId,ItemName
1     ,'test'
2     ,'test2'
3     , 'test3'

and second table is (Important table),this table tell us that ItemId has what specifications? For example ItemId 1 has specs 5 and 6 and 7

tbl_Spec

ItemId , SpecId
1      ,5
1      ,6
1      ,7
2      ,5
2      ,8
3      ,5
3      ,7

How can I select Items that have both SpecId 5 and 7

the result must be :

ItemId
1
3

SQL In (...) do the OR as default, but I want something with And Function.

My DBMS is SQL Server 2008

Answer 1

I'm sure there must be more elegant ways, but this should give you what you want (EDIT: fixed as per Michaeł Powaga's suggestion).

SELECT ItemId
FROM tbl_Spec
WHERE SpecId=5 OR SpecId=7
GROUP BY ItemId
HAVING COUNT(DISTINCT SpecId)=2

ps Ali , if you need a more easily expandable solution, have you seen Mikael Eriksson's answer?

Answer 2

select itemid from
(
    select itemid from tbl_spec where specid = 5
) subset1 inner join
(
    select itemid from tbl_spec where itemid = 7
) subset2 on subset1.itemid = subset2.itemid

Answer 3

declare @T table
(
  ItemId int,
  SpecId int
)

insert into @T values
(1      ,5),
(1      ,6),
(1      ,7),
(2      ,5),
(2      ,5),
(2      ,8),
(3      ,5),
(3      ,7),
(4      ,5),
(4      ,5)

;with C(SpecId) as
(
  select 5 union all
  select 7
)
select T.ItemId
from @T as T
  inner join C
    on T.SpecId = C.SpecId
group by T.ItemId
having count(distinct T.SpecId) = (select count(*) from C)

Result:

ItemId
1
3

Answer 4

This will give the desired output you requested, but I'm not 100% sure if this is what you are asking for.

select distinct itemID
from tbl_Spec
where SpecId in (5,7)

Answer 5

Do the following sql query

select ItemId from tbl_Spec where SpecId in (5,7)

Answer 6

select distinct ItemId from tbl_Item, tbl_Spec 
where tbl_Item.ItemId=tbl_Spec.ItemId 
and tbl_SPec.SpecId not in (select SpecId from tbl_Spec where SpecId not in (5,7))

I hope it works for you.

Answer 7

select * from (select Count(ItemID)Counted from tbl_Spec where Itemid in (select Itemid  from tbl_Item )and SpecId in(5,7) group by ItemID) a where Counted>=2