I have two table called
Supplier Table
Customer Table
there are no relation between them
First Table Customer have this data
Customer Table
Second Table Supplier have this data
Supplier Table
I need to see data as this
SupplierID CustomerName
1 Yahia
1 Ahmed
1 Ali
2 Yahia
2 Ahmed
2 Ali
3 Yahia
3 Ahmed
3 Ali
Note That No Relation Between Two table
can achieve this relation?
Your question is not very clear but it seems you want a cartesian product of those two tables. This is easily done with a cross join.
select *
from supplier s
cross join Customer c
You might want this
select
SupplierID,CustomerName
from
Supplier
cross join
Customer
If you want to multiply each rows of a table with every rows of an other table, you can use CROSS JOIN
SELECT S.SupplierID, C.CustomerName
FROM supplier S
CROSS JOIN Customer C
MSDN about CROSS JOIN
Related
I have 2 tables: Person and House with 1-n relation.
I want to the result return as picture below:
Row always have a Person column with a null House column.
Thanks.
you can use unionall to join the result set with person table something like
select p.name,h.name as housename from person p join house h on p.id=h.personid
union all (select name,null from person)
order by name,housename
thanks in advance for any help on this, I am a bit of a newbie to MS SQL and I want to do something that I think is achievable but don't have the know how.
I have a simple table called "suppliers" where I can do (SELECT id, name FROM suppliers ORDER BY id ASC)
id
name
1
ACME
2
First Stop Business Supplies
3
All in One Supply Warehouse
4
Farm First Supplies
I have another table called "products"
id
name
supplier_id
1
Item 1
2
2
Item 2
1
3
Item 3
1
4
Item 4
3
5
Item 5
2
I want to list all the suppliers and get the total amount of products for each supplier if that makes sense on the same row? I am just not sure how to pass the suppliers.id through the query to get the count.
I am hoping to get to this:
id
name
total_products
1
ACME
2
2
First Stop Business Supplies
2
3
All in One Supply Warehouse
1
4
Farm First Supplies
0
I really appreciate any help on this.
Three concepts to grasp here. Left Join, group by, and Count().
select s.id, s.name, Count(*) as total_products
from suppliers s
left join products p on s.id=p.supplier_id --the left join gets your no matches
group by s.id, s.name
left join is a join where all of the values from the first table are kept even if there are no matches in the second.
Group by is an aggregation tool where the columns to be aggregated are entered.
Count() is simply a count of transactions for the grouped columns.
Try this :-
SELECT id, name, C.total_products
FROM Suppliers S
OUTER APPLY (
SELECT Count(id) AS total_products
FROM Products P
WHERE P.supplier_id = S.id
) C
I have two tables with the following rows
Table A (transaction)
Order Seller Customer
1 300 500
Table B (Persons)
PersonID FullName
300 Peter White
500 Scott Bold
I want a result like this
Order Seller Customer FullName (Seller) FullName (customer)
1 300 500 Peter White Scott Bold
I've tried multiple things however which makes more sense is a join a table twice, however I'm getting:
Ambiguous column name
This is SQL Server 2019.
Basically I'm looking to retrieve info from the same table instead of creating additional tables. Is that possible? If yes, how do you do? Thank you in advance.
As #jarlh wrote in comment:
select t.order, t.seller, t.customer, sel.fullname, cust.fullname
from transaction t
join persons sel -- sel is an alias to persons table
on sel.personid = t.seller
join persons cust
on cust.personid = t.customer;
Query with join will return the result as long as both seller and customer exist in persons table -- here it should as source table names transactions :).
I have another form of query it still join table B twice.
This is archaic syntax which I don't recommend but for beginner know the concept of JOIN:
select t.*,B.FullName as FullName (customer) from
(
select A.Order,A.Seller,A.Customer,B.FullName as FullName(Seller)
from A,B where A.Seller=B.PersionID
) t, B where t.Customer=B.PersionID
The proper way of JOIN:
select t.*,B.FullName as FullName (customer) from
(
select A.Order,A.Seller,A.Customer,B.FullName as FullName(Seller)
from A JOIN B ON A.Seller=B.PersionID
) t JOIN B ON t.Customer=B.PersionID
Hoping this can help you.
I was trying to update table columns from another table.
In person table, there can be multiple contact persons with same inst_id.
I have a firm table, which will have latest 2 contact details from person table.
I am expecting the firm tables as below:
If there is only one contact person, update person1 and email1. If there are 2, update both. If there is 3, discard the 3rd one.
Can someone help me on this?
This should work:
;with cte (rn, id, inst_id, person_name, email) as (
select row_number() over (partition by inst_id order by id) rn, *
from person
)
update f
set
person1 = cte1.person_name,
email1 = cte1.email,
person2 = cte2.person_name,
email2 = cte2.email
from firm f
left join cte cte1 on f.inst_id = cte1.inst_id and cte1.rn = 1
left join cte cte2 on f.inst_id = cte2.inst_id and cte2.rn = 2
The common table expression (cte) used as a source for the update numbers rows in the person table, partitioned by inst_id, and then the update joins the cte twice (for top 1 and top 2).
Sample SQL Fiddle
I think you don't have to bother yourself with this update, if you rethink your database structure. One great advantage of relational databases is, that you don't need to store the same data several times in several tables, but have one single table for one kind of data (like the person's table in your case) and then reference it (by relationships or foreign keys for example).
So what does this mean for your example? I suggest, to create a institution's table where you insert two attributes like contactperson1 and contactperson2: but dont't insert all the contact details (like email and name), just the primary key of the person and make it a foreign key.
So you got a table 'Person', that should look something like this:
ID INSTITUTION_ID NAME EMAIL
1 100 abc abc#inst.com
2 101 efg efg#xym.com
3 101 ijk ijk#fg.com
4 101 rtw rtw#rtw.com
...
And a table "Institution" like:
ID CONTACTPERSON1 CONTACTPERSON2
100 1 NULL
101 2 3
...
If you now want to change the email adress, just update the person's table. You don't need to update the firm's table.
And how do you get your desired "table" with the two contact persons' details? Just make a query:
SELECT i.id, p1.name, p1.email, p2.name, p2.email
FROM institution i LEFT OUTER JOIN person p1 ON (i.contactperson1 = p1.id)
LEFT OUTER JOIN person p2 ON (i.contactperson2 = p2.id)
If you need this query often and access it like a "table" just store it as a view.
I created a database in ms sql , in the database I have three category of persons namely staff, customers, suppliers whom I stored in different tables create serial unique id for each.
Now these persons id are stored under person_id and a column names person type which stores whether its a staff, custimer or supplier in the transaction table, The problem lies in selecting the records from the transaction table like this pseudo code
Select t.*,s.na as staff,sp.name as supplier, c.name as customer
From Trans t
left join Staff s on s.id = t.pid
left join Suppliers sp on sp.id = t.pid
left join Customers c on c.id = t.pid
This returns one row, instead of at least 3 or more, How do I solve this problem
My trans table
person_id Person_type Trans_id
1 staff 1
1 customer 2
2 customer 3
3 suppler 4
1 staff 5
Expected output
person_name Trans_id
james 1
mark 2
dan 3
jude 4
james 5
Staff, Customers, and suppliers are stored in their different tables
That's what the Join does, combine data from multiple tables into one result row. If you want to "keep the rows", not combine them, you can use UNION
(
Select t.* From Trans t
left join Staff s on s.id = t.pid
)
UNION
(
Select t.* From Trans t
left join Suppliers sp on sp.id = t.pid
)
UNION
(
Select t.* From Trans t
left join Customers c on c.id = t.pid
)
This will get you the multiple rows you want BUT still not sure you have defined it right. I see you are only taking columns from Trans, so you're not getting any data from the other tables. And you're doing left outer joins so the other tables won't affect the selection. So I think it's just that same as selecting from just Trans.
If what you want is data from Trans where there is corresponding entry in the other tables, then do the UNION, but also change the outer joins to inner.