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.
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
I have two hive table's. And both tables have one column column. There are some few rows which value is same in both tables
Now my requirement is join the two tables and exclude the common records from second table based on common column.
For example,
Table a:
Name. City. Country
Devid. Hyd. Ind
Steve. London. UK
John. Bangalore. Ind
Table B
Name. City. Country
Xxxx. Xxxxx. Ind
Yyyyy. Yyyy. US
Zzzz. Zzzzz. UK
Now my required output is
Name. City. Country
Devid. Hyd. Ind
Steve. London. UK
John. Bangalore. Ind
Yyyyy. Yyyy. US
I tried following logic
Select a.* From A a union
Select t.* From (
Select c.* From table B b right join table A c on
b.country = c.coubtry
Where b.id is null) t;
This query not completing, keep on running. Any workaround needed?
Please help me out guys.
Try the below code:
SELECT * FROM A
UNION
SELECT * FROM B
WHERE Country NOT IN
(SELECT DISTINCT Country FROM A)
I may be overthinking this but I have not managed to figure it out or find a solution, so I'm hoping for a pointer in the right direction. I tried using the Select ColumnA AS Column B etc but it's not doing what I want.
I have 2 tables, scenario examples below
Table 1 (Vehicle)
VehicleID (001)
VehicleMake (Ford)
VehicleModel (Falcon)
VehicleExCleanEmpID (005)
VehicleIntCleanEmpID (003)
Table 2 (Employee)
EmpID (005)
EmpName (Dave)
The scenario being that a vehicle is cleaned internally or externally by any one of a pool of employees shown by the relevant ID in the Vehicles table.
I want to show in a query VehicleID, InsideCleanName, ExternalCleanName rather than showing the employee's ID.
So end up with results similar to this
VehicleID InsideCleanName ExternalCleanName
------------------------------------------------
001 Bob Dave
002 Sue Dave
003 John Sid
Thanks for any tips and or help
THat seems like a pretty simple query with two inner joins to the Employee table - something like this:
SELECT
v.VehicleId,
InsideCleanName = e1.EmpName,
ExternalCleanName = e2.EmpName
FROM
dbo.Vehicle v
INNER JOIN
dbo.Employee e1 ON v.VehicleIntCleanEmpId = e1.EmpID
INNER JOIN
dbo.Employee e2 ON v.VehicleExCleanEmpId = e2.EmpID
Joining to the Employee e1 table is giving you the employee who was responsible for the inside cleaning, while joining a second time, to Employee e2 gives you the one responsible for the external cleaning.
Join the two table with EmpId and select the columns you want similar to the code below:
select column1, column2 from table1 inner join table2 on table1.EmpId = table2.EmpId
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
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.