Interview Questions
1. What is Logical Fragmentation?
SQL Server uses 8KB Pages to store data on disk. When a clustered index is created on a table, SQL Server creates a b-tree data
structure for the index and links all data pages at the leaf level of the tree in a logical order by using a doubly linked list. Logical fragmentation occurs when the pages in this doubly linked list are not contiguous in the index, meaning that indexes have pages
in which the logical ordering of pages, which is based on the key value, does not match the physical ordering inside the data file.
Submit an interview question
Submitted questions and answers are subject to review and editing, and may or may not be selected for posting, at the sole discretion of w3Sniff.
Get Started
Comments
Leave a Comment