The limitations of the missing index feature – It does not specify an order for columns to be used in an index

In the last post you saw that the missing index feature does not consider trivial plans. In this blog I will explain another limitation of the missing index feature - it does not specify an order for columns to be used in an index. SQL Server can only benefit from a row store index if the key columns are in the correct order. The order of the columns of an index determines whether SQL Server chooses an index scan or seek. Scanning an index simply means that the storage engine of SQL Server will read all index pages and filter the desired records afterwards (residual predicate)