Showing posts with label longest. Show all posts
Showing posts with label longest. Show all posts

Friday, March 16, 2012

"Tracking"

OK. For DDL, please refer to the classical Northwind ORDERS table,
problem/challenge, find the longest duration (start_date and
end_date), during which, no orders were placed.

FYI, column names by the order of colid per syscolumns:
OrderID
CustomerID
EmployeeID
OrderDate
RequiredDate
ShippedDate
ShipVia
Freight
ShipName
ShipAddress
ShipCity
ShipRegion
ShipPostalCode
ShipCountry

Any idea/approach? TIA.Does this help?

select o1.OrderDate, o2.OrderDate, DATEDIFF( day, o1.OrderDate,
o2.OrderDate) as days_between
from dbo.Orders o1, dbo.Orders o2
where o1.OrderDate < o2.OrderDate
and not exists
(select * from dbo.Orders o3
where o3.OrderDate < o2.OrderDate
and o1.OrderDate < o3.OrderDate)
group by o1.OrderDate, o2.OrderDate
order by days_between desc

"DonLi" <donli@.yahoo.com> wrote in message
news:9a172893.0404051228.4a675061@.posting.google.c om...
> OK. For DDL, please refer to the classical Northwind ORDERS table,
> problem/challenge, find the longest duration (start_date and
> end_date), during which, no orders were placed.
> FYI, column names by the order of colid per syscolumns:
> OrderID
> CustomerID
> EmployeeID
> OrderDate
> RequiredDate
> ShippedDate
> ShipVia
> Freight
> ShipName
> ShipAddress
> ShipCity
> ShipRegion
> ShipPostalCode
> ShipCountry
> Any idea/approach? TIA.