Question

A table has a clustered index defined on its primary key column "OrderID". What does this specifically imply about how the table's data rows are physically stored on disk?

Q: Answer-A table has a clustered index defined on its primary key column 'OrderID'. What does this specifical...

A clustered index determines the actual physical storage order of a tables data rows the rows themselves are sorted and stored on disk according to the clustered index key here, OrderID. Because data can only be physically arranged in one order at a time, a table can have at most ONE clustered index. This is fundamentally different from a non-clustered index, which maintains a separate structure containing the indexed columns plus pointers row locators back to the actual data rows which remain stored in whatever order the clustered index dictates, or unsorted if there is no clustered index a table can have many non-clustered indexes.

A The data rows are stored in a completely random physical order, unrelated to OrderID

B The table can have multiple clustered indexes, one for each frequently queried column

C A separate index structure is stored with pointers back to data rows stored elsewhere, unrelated to physical row order

D The actual data rows themselves are physically sorted and stored on disk in OrderID order — a table can have only one clustered index, since data can only be physically ordered one way

E The index is stored entirely in RAM and never persisted to disk

Practice Next