Tagged: Nonclustered Index


The Importance of First Column in Nonclustered Index

Does it matter which column is first in an Index? Yes it does, simply because using different columns can result in different execution plans.  Introduction Let’s consider the below select statement – first we will create an index named [IX_OrderDate_ProductKey] on OrderDate and ProductKey and then an index [IX_ProductKey_OrderDate] on ProductKey and OrderDate.