Identify the missing word(s) in the following sentence within the context of Microsoft Azure. When doing performance tuning in Azure SQL, understanding the importance of statistics is critical. Statistics are stored in the user database as binary large objects (blobs). These blobs contain statistical information about the distribution of data values in one or more columns of a table or indexed view. The query optimizer uses column and index statistics in order to determine [?], which is the number of rows a query is expected to return. [?] estimates are then used by the query optimizer to generate the execution plan.