Microsoft SQL Server 2014 Unleashed

Clustered Tables

A clustered table is a table that has a clustered index defined on it. When you create a clustered index, the data rows in the table are physically sorted in the order of the columns in the index key. The data pages are chained together in a doubly linked list (each page points to the next page and to the previous page). In a nonclustered heap table, data pages are not linked. Only index pages within a level are linked in this manner to allow for ordered scans of the data in an index level. Because the data pages of a clustered table constitute the leaf level of the clustered index, they are chained as well. This allows for an ordered table scan. The page pointers are stored in the page header. Figure 31.14 shows a simplified ...