“SQL inner joins the right way”

rails, Uncategorized

The right way
————————————-
select s.CompanyName
from Suppliers as s
where exists
(
select * from products p
inner join categories c on p.CategoryID = c.CategoryID
where c.CategoryName = “Seafood”
and p.SupplierID=s.SupplierID
)
—————————————-


The wrong way
————————————————
SELECT DISTINCT Suppliers.CompanyName
FROM Suppliers INNER JOIN (Categories INNER JOIN Products ON
Categories.CategoryID = Products.CategoryID) ON Suppliers.SupplierID =
Products.SupplierID
WHERE (((Categories.CategoryName)=”Seafood”))
————————————————

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