Hessel de Walle's Blog

One of the ways to speed up an SQL query is putting the smallest table first in the FROM clause and so on. How is Crystal Reports dealing with this? For the examples I used the NorthWind database. I picked the tables Order_Details , Orders and Customers . I linked the table manually by dragging a line from Order_Details->OrderID to Orders->OrderID and from Orders->CustomerID to Customers->CustomerID . When we would now drag the fields Customers->CompanyName and Order_Details->Quantity to our report our SQL Query would look like this: SELECT `Customers`.`CompanyName`, `Order_Details`.`Quantity` FROM   (`Order Details` `Order_Details` INNER JOIN `Orders` `Orders` ON `Order_Details`.`OrderID`=`Orders`.`OrderID`) INNER JOIN `Customers` `Customers` ON `Orders`.`CustomerID`=`Customers`.`CustomerID` Now back to the Links window of the Database Expert . Remove the links. Link the table again manually by dragging a line from Order...