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Brug af COALESCE i SQL-visning

REDIGER :Ændret svar til at inkludere oprettelse af visning.

/* Set up sample data */ create table Customers ( CustomerId int, CustomerName VARCHAR(100) ) create table Orders ( CustomerId int, OrderName VARCHAR(100) ) insert into Customers (CustomerId, CustomerName) select 1, 'John' union all select 2, 'Marry' insert into Orders (CustomerId, OrderName) select 1, 'New Hat' union all select 1, 'New Book' union all select 1, 'New Phone' go /* Create the view */ create view OrderView as select c.CustomerName, x.OrderNames from Customers c cross apply (select stuff((select ',' + OrderName from Orders o where o.CustomerId = c.CustomerId for xml path('')),1,1,'') as OrderNames) x go /* Demo the view */ select * from OrderView go /* Clean up after demo */ drop view OrderView drop table Customers drop table Orders go

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