Sitecore Incremental Publishing Revealed

After seen a post in Sitecore Community forum, I thought of writing this post.

I will try to explain how Sitecore Incremental publishing works internally in Sitecore


1) Sitecore item created/edited/deleted

Sitecore will write an entry to "History" table

Note : There is an exception in some cases, where entry was NOT written to History table.
See Cases where an Entry was not written to History table... (coming soon)


2) Incremental Publishing task executed

• In "Properties" table, there is an entry to store Last Incremental Publishing run time.
• Sitecore goes to "Properties" table and take the above setting value.
• Then, go to Publish Queue table and take all the entries which is entered into that table after the Last Incremental Publish runtime property value.
• Then, it publishes those items one after another, from oldest to latest
• At the end of the above task, Sitecore Updates the entry in the "Properties" table with the current timestamp.

Practical Scenario :

1) Edit "/sitecore/content/home" item

2) Entry added to History table

3) Run an Incremental Publish

4) Sitecore retrieves the Last Publish time for the language, and publish all the items/rows added to Publish Queue table after that time

 

5) After publish end, Update/Write Last Publish time entry in the Properties table

Extra Readings :

How Sitecore History table is Maintained...(coming soon)
Cases where an Entry was not written to History table... (coming soon)