I make filesystem backups of /data/ and am trying to restore my contacts. Contacts appear to be stored in /data/data/user_de/0/com.android.providers.contacts/, specifically its database/contacts2.db.
Manually restoring this directory however does not appear to work. The data is 1:1 the same but, upon opening the contacts app, all contacts are wiped from the db.
How can I restore contacts from a filesystem backup such that they're not wiped by Android?
In order to restore contacts (and other providers for that matter it seems), you must restore all content com.android.provider.* directories under both /data/data/ and /data/user_de/0/.
When I do that, all my contacts are in the contacts app as they should be. SMS messages, call history etc. are also restored.
(It is possible there is a specific subset of directories that are sufficient aswell but I didn't pursue this further as you'd usually want SMS etc. to also be restored, so might as well restore all content providers.)
