create two tables using one - sql

Question

CREATE TABLE ItemsOfStores ( Item int, Store int );
For my example above, that data would contain:
INSERT INTO ItemsOfStores (Item,Store)
VALUES (1,1),(1,3),(4,1),(4,3),(5,1),(5,3),(2,1),
(2,2),(2,4),(3,1),(3,2),(3,4);
I need the SQL to insert the results into 2 tables:
CREATE TABLE StoreGroups ( GroupId int, Store int )
CREATE TABLE ItemsOfGroups ( GroupId int, Item int )
In my example above, items 1, 4 and 5 are at stores 1 and 3, then there would be a group of
stores composed of stores 1 and 3, I'll call that group 1. So group 1 holds stores 1 and 3, so that would put (1,1),(1,3) into StoreGroups,
and the items 1, 4 and 5 are in that group, so (1,1),(1,4),(1,5) would go into ItemsOfGroups.
Also in my example, items 2 and 3 are at stores 1, 2 and 4, then there would be a second group
of stores composed of stores 1, 2 and 4, I'll call that group 2. So (2,1),(2,2),(2,4) would go into StoreGroups, and (2,2),(2,3) would go into ItemsOfGroups.
So the final results would of this small example would fill StoreGroups
with (1,1),(1,3),(2,1),(2,2),(2,4),
and ItemsOfGroups with (1,1),(1,4),(1,5),(2,2),(2,3)

Answer 1

I guess you want something like this.
CREATE TABLE ItemsOfStores ( Item int, Store int );
INSERT INTO ItemsOfStores (Item,Store)
VALUES (1,1),(1,3),(4,1),(4,3),(5,1),(5,3),(2,1),
(2,2),(2,4),(3,1),(3,2),(3,4);
CREATE TABLE StoreGroups ( GroupId int, Store int );
CREATE TABLE ItemsOfGroups ( GroupId int, Item int );
Insert into StoreGroups
SELECT z.GroupID, value
FROM (
Select ROW_NUMBER() OVER(ORDER BY x.Store ASC)as GroupID, x.Store , x.Item
from
(
select
T3.Store,
stuff((SELECT ', ' + cast(Item as varchar(10))
FROM (
select Item,
stuff((SELECT ', ' + cast(Store as varchar(10))
FROM ItemsOfStores t2
where t2.Item = t1.Item
order by Store
FOR XML PATH('')),1,1,'') as Store
from ItemsOfStores t1
group by Item
)t4
where t4.Store = t3.Store
order by Item
FOR XML PATH('')),1,1,'')
as Item
from (
select Item,
stuff((SELECT ', ' + cast(Store as varchar(10))
FROM ItemsOfStores t2
where t2.Item = t1.Item
order by Store
FOR XML PATH('')),1,1,'') as Store
from ItemsOfStores t1
group by Item
) t3
group by T3.Store
) x
)z
CROSS APPLY STRING_SPLIT(z.Store, ',');
Select * from StoreGroups
Returns:
GroupId Store
1 1
1 2
1 4
2 1
2 3
same logic:
Insert into ItemsOfGroups
-- Use String Split (SQL2016+) function to split merged colums back into seperate values with their related GroupID
SELECT z.GroupID, value
FROM (-- Add GroupID which is related to both merged Item rows and merged store rows
Select ROW_NUMBER() OVER(ORDER BY x.Store ASC)as GroupID, x.Store , x.Item
from
( -- Merge Item values into one row (grouped by Grouped result of Store)
select Store,
stuff((SELECT ', ' + cast(Item as varchar(10))
FROM (
select Item,
stuff((SELECT ', ' + cast(Store as varchar(10))
FROM ItemsOfStores t2
where t2.Item = t1.Item
order by Store
FOR XML PATH('')),1,1,'') as Store
from ItemsOfStores t1
group by Item
)t4
where t4.Store = t3.Store
order by Item
FOR XML PATH('')),1,1,'') as Item
from ( -- Merge Store values into one row (grouped by Item)
select Item,
stuff((SELECT ', ' + cast(Store as varchar(10))
FROM ItemsOfStores t2
where t2.Item = t1.Item
order by Store
FOR XML PATH('')),1,1,'') as Store
from ItemsOfStores t1
group by Item
) t3
group by T3.Store
) x
)z
CROSS APPLY STRING_SPLIT(z.Item, ',');
Select * from ItemsOfGroups
Returns:
GroupId Item
1 2
1 3
2 1
2 4
2 5