When should you perform a rebuild of the Link Database?

Rebuilding the Link Database is critical for maintaining the integrity of the linking structure within Sitecore. It is particularly important to perform this task as part of routine maintenance or after significant changes to ensure that any new or modified links are updated in the database. When major updates occur—such as mass publishing, bulk item changes, or structural alterations within the content tree—the link references may become outdated or broken.

By rebuilding the Link Database in these scenarios, you can refresh the mappings of links to ensure that all items point correctly to their associated links, thus preventing user experience issues like broken links or incorrect navigations. This process ensures that the Sitecore environment remains efficient and that link data is accurate and reliable.

While there are advantages to updating the Link Database after content is published or periodically (as seen in some of the other choices), the most effective approach is to do so after significant changes or as a part of a planned maintenance schedule to minimize any risk of outdated link information affecting users' interactions with the website.