converting a list subquery to an inner join

#1

Quote:

From this page: http://www.microsoft.com/technet/pro.../c0918260.mspx

We see:
SELECT CompanyName
FROM Customers
WHERE CustomerID IN
(SELECT CustomerID FROM Orders WHERE OrderDate > '1/1/95')

And I assume the following inner joins are equivalent:

SELECT CompanyName
FROM Customers, Orders
WHERE Customers.CustomerID = Orders.CustomerID
GROUP BY CompanyName

as well as:

SELECT DISTINCT CompanyName
FROM Customers, Orders
WHERE Customers.CustomerID = Orders.CustomerID

but I would like to make sure.

#2

metaperl wrote:

Quote:

From this page: http://www.microsoft.com/technet/pro.../c0918260.mspx

We see:
SELECT CompanyName
FROM Customers
WHERE CustomerID IN
(SELECT CustomerID FROM Orders WHERE OrderDate > '1/1/95')

And I assume the following inner joins are equivalent:

SELECT CompanyName
FROM Customers, Orders
WHERE Customers.CustomerID = Orders.CustomerID
GROUP BY CompanyName

as well as:

SELECT DISTINCT CompanyName
FROM Customers, Orders
WHERE Customers.CustomerID = Orders.CustomerID

but I would like to make sure.

I'm not sure what you are asking for, but the first query is obviously
not equivalent with the other two (with the info given).

/Lennart

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converting a list subquery to an inner join

comp.databases comp.databases

converting a list subquery to an inner join - 07-17-2007 , 11:53 AM

Re: converting a list subquery to an inner join - 07-18-2007 , 06:49 AM