Merge #1866

1866: v0.29: Soft deletion r=guimachiavelli a=guimachiavelli

Closes #1852

Co-authored-by: gui machiavelli <[email protected]>
Co-authored-by: gui machiavelli <[email protected]>

Author: bors[bot]

learn/advanced/storage.md

@@ -71,3 +71,9 @@ These metrics are highly dependent on the machine that is running Meilisearch. R
 It is important to note that **there is no reliable way to predict the final size of a database**. This is true for just about any search engine on the market—we're just the only ones saying it out loud.
 
 Database size is affected by a large number of criteria, including settings, relevancy rules, use of facets, the number of different languages present, and more.
+
+## Soft deletion
+
+Meilisearch renders deleted documents inaccessible to all users but does not immediately remove them from the database. This is a common optimization technique called soft deletion. Soft deleted documents are permanently deleted during a later update, depending on your index size and the available disk space. It might be important to check how soft deletion interacts with data retention legislation relevant to your application.
+
+Soft deletion also affects document updates: when you update a document, Meilisearch removes the current record and creates a new document with updated data.