Compare column data

Hi Experts,

Here is my table:
Account (AccountId, UserId, Currency)
                 1                   1            USD
                 2                    1           USD
                 3                    2           EUR
                 4                    1           USD
                 5                    2           USD

I need to compare the currencies because 1 user must only have 1 currency.
So, in my  example, User1 currency is USD (no problem) so I can  return the currency of User1.
But User2 has 2 currencies so I need to throw an  error.

Thanks in advance for your help.
                 
LVL 9
nouloukAsked:
Who is Participating?

[Webinar] Streamline your web hosting managementRegister Today

x
 
chiragkhabariaConnect With a Mentor Commented:
Something like this

PS Not i have added some records in the table for more testing...

The query will return all the user name whoese has more then one currency in the Currency column...



-- Create the Table Varaible for checking..
Declare @Account Table
(
      AccountId int,
      UserId int,
      Currency varchar(10)
)

-- Insert the Values in the TAble VAraible for testing.
Insert @Account
 Select 1,1, 'USD' Union All
Select 2, 1,'USD' Union All
Select 3, 2,'EUR' Union All
Select 4, 1,'USD' Union All
Select 6, 2,'USD' Union All
Select 7, 1,'EUR' Union All
Select 8, 3,'USD' Union All
Select 9, 3,'USD' Union All
Select 10, 4 ,'USD' Union All
Select 11, 4,'EUR'


-- Now this is the query which will extract the duplicate records

Select Distinct UserID  From @Account a
Where UserID In
(
      Select  UserID From @Account b where a.UserID = b.UserID And a.Currency <> b.Currency
)

0
 
YttribiumConnect With a Mentor Commented:
Why not have the User Table contain the Currency, and join it to this Account table?

Like
TABLE: [User]
ID
Name
Currency

TABLE [Account]
AccountID
UserID


VIEW AccountCurrency
SELECT     Account.AccountID, Account.UserID, User.Currency
FROM         Account INNER JOIN
                      User ON Account.UserID = User.UserID
0
All Courses

From novice to tech pro — start learning today.