Update documentation: NoteDb is the only storage format in 3.x

Change-Id: I9dd3c66b66b507608e693e511e971c437596b93d

3 files changed, 12 insertions, 35 deletions

diff --git a/Documentation/intro-user.txt b/Documentation/intro-user.txt
index a4271dee88..4820f23229 100644
--- a/Documentation/intro-user.txt
+++ b/Documentation/intro-user.txt
@@ -517,9 +517,6 @@ topics, a change can have multiple hashtags, and they are only used for
 informational grouping; changes with the same hashtags are not necessarily
 submitted together.
 
-The hashtag feature is only available when running under
-link:note-db.html[NoteDb].
-
 .Set Hashtag on Push
 ----
   $ git push origin HEAD:refs/for/master%t=stable-bugfix
diff --git a/Documentation/note-db.txt b/Documentation/note-db.txt
index 49f8049c8b..0bacca4860 100644
--- a/Documentation/note-db.txt
+++ b/Documentation/note-db.txt
@@ -1,8 +1,9 @@
 = Gerrit Code Review - NoteDb Backend
 
-NoteDb is the next generation of Gerrit storage backend, which replaces the
-traditional SQL backend for change, account and group metadata with storing
-data in the same repository as code changes.
+NoteDb is the storage backend for code review metadata. It is based on
+Git, so code reviews are stored together with the code under review.
+NoteDb replaced the traditional SQL backend for change, account and group
+metadata that was used in the 2.x series.
 
 .Advantages
 - *Simplicity*: All data is stored in one location in the site directory, rather
@@ -21,33 +22,19 @@ data in the same repository as code changes.
 - *New features*: Enables simple federation between Gerrit servers, as well as
   offline code review and interoperation with other tools.
 
-== Current Status
-
-- Storing change metadata is fully implemented in the 2.15 release, and is the
-  default for new sites.
-- Admins may use an link:#offline-migration[offline] or
-  link:#online-migration[online] tool to migrate change data in an existing
-  site from ReviewDb.
-- Storing link:config-accounts.html[account data] is fully implemented in the
-  2.15 release. Account data is migrated automatically during the upgrade
-  process by running `gerrit.war init`.
-- Storing link:config-groups.html[group metadata] is fully implemented
-  in the 2.16 release. Group data is migrated automatically during
-  the upgrade process by running `gerrit.war init`
-- Account, group and change metadata on the servers behind `googlesource.com` is fully
-  migrated to NoteDb. In other words, if you use
-  link:https://gerrit-review.googlesource.com/[gerrit-review], you're already
-  using NoteDb.
-- NoteDb is the only database format supported by Gerrit 3.0. The change data
-  migration tools are only included in Gerrit 2.15 and 2.16; they are not
-  available in 3.0.
-
 For an example NoteDb change, poke around at this one:
 ----
   git fetch https://gerrit.googlesource.com/gerrit refs/changes/70/98070/meta \
       && git log -p FETCH_HEAD
 ----
 
+== Current Status
+
+NoteDb is the only database format supported by Gerrit 3.0+. The
+change data migration tools are only included in Gerrit 2.16; they are
+not available in 3.0, so any upgrade from Gerrit 2.x to 3.x must go through
+2.16 to effect the NoteDb upgrade.
+
 [[migration]]
 == Migration
 
diff --git a/Documentation/rest-api-changes.txt b/Documentation/rest-api-changes.txt
index 6ecaefefe0..952551a0d1 100644
--- a/Documentation/rest-api-changes.txt
+++ b/Documentation/rest-api-changes.txt
@@ -989,8 +989,6 @@ If the change has no assignee the response is "`204 No Content`".
 Returns a list of every user ever assigned to a change, in the order in which
 they were first assigned.
 
-[NOTE] Past assignees are only available when NoteDb is enabled.
-
 .Request
 ----
   GET /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/past_assignees HTTP/1.0
@@ -2346,8 +2344,6 @@ This allows users to "highlight" changes in their dashboard
 
 Gets the hashtags associated with a change.
 
-[NOTE] Hashtags are only available when NoteDb is enabled.
-
 .Request
 ----
   GET /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/hashtags HTTP/1.0
@@ -2376,8 +2372,6 @@ As response the change's hashtags are returned as a list of strings.
 
 Adds and/or removes hashtags from a change.
 
-[NOTE] Hashtags are only available when NoteDb is enabled.
-
 The hashtags to add or remove must be provided in the request body inside a
 link:#hashtags-input[HashtagsInput] entity.
 
@@ -5837,8 +5831,7 @@ Only set if link:#detailed-labels[detailed labels] are requested.
 |`reviewer_updates`|optional|
 Updates to reviewers set for the change as
 link:#review-update-info[ReviewerUpdateInfo] entities.
-Only set if link:#reviewer-updates[reviewer updates] are requested and
-if NoteDb is enabled.
+Only set if link:#reviewer-updates[reviewer updates] are requested.
 |`messages`|optional|
 Messages associated with the change as a list of
 link:#change-message-info[ChangeMessageInfo] entities. +