Update the docs to reflect lack of MySQL support

Now MySQL is no longer supported, we need to change the docs

3 files changed, 1 insertions, 33 deletions

diff --git a/doc/development/architecture.md b/doc/development/architecture.md
index d817d513173..a43a40152db 100644
--- a/doc/development/architecture.md
+++ b/doc/development/architecture.md
@@ -695,7 +695,7 @@ We've also detailed [our architecture of GitLab.com](https://about.gitlab.com/ha
 [runner-gdk]: https://gitlab.com/gitlab-org/gitlab-development-kit/blob/master/doc/howto/runner.md
 [database-migrations-omnibus]: https://docs.gitlab.com/omnibus/settings/database.html#disabling-automatic-database-migration
 [database-migrations-charts]: https://docs.gitlab.com/charts/charts/gitlab/migrations/
-[database-migrations-source]: ../update/upgrading_from_source.md#14-install-libs-migrations-etc
+[database-migrations-source]: ../update/upgrading_from_source.md#13-install-libs-migrations-etc
 [certificate-management-omnibus]: https://docs.gitlab.com/omnibus/settings/ssl.html
 [certificate-management-charts]: https://docs.gitlab.com/charts/installation/tls.html
 [certificate-management-source]: ../install/installation.md#using-https
diff --git a/doc/development/rake_tasks.md b/doc/development/rake_tasks.md
index 28a12572961..4fc10b6af5c 100644
--- a/doc/development/rake_tasks.md
+++ b/doc/development/rake_tasks.md
@@ -80,30 +80,6 @@ There are a few environment flags you can pass to change how projects are seeded
 - `LARGE_PROJECTS`: defaults to false. If set will clone 6 large projects to help with testing.
 - `FORK`: defaults to false. If set to `true` will fork `torvalds/linux` five times. Can also be set to an existing project full_path and it will fork that instead.
 
-### Notes for MySQL
-
-Since the seeds would contain various UTF-8 characters, such as emojis or so,
-we'll need to make sure that we're using `utf8mb4` for all the encoding
-settings and `utf8mb4_unicode_ci` for collation. Please check
-[MySQL utf8mb4 support](../install/database_mysql.md#mysql-utf8mb4-support)
-
-Make sure that `config/database.yml` has `encoding: utf8mb4`, too.
-
-Next, we'll need to update the schema to make the indices fit:
-
-``` shell
-sed -i 's/limit: 255/limit: 191/g' db/schema.rb
-```
-
-Then run the setup script:
-
-``` shell
-bundle exec rake setup
-```
-
-To make sure that indices still fit. You could find great details in:
-[How to support full Unicode in MySQL databases](https://mathiasbynens.be/notes/mysql-utf8mb4)
-
 ## Run tests
 
 In order to run the test you can use the following commands:
diff --git a/doc/development/swapping_tables.md b/doc/development/swapping_tables.md
index 29cd6a43aff..5c62900dbff 100644
--- a/doc/development/swapping_tables.md
+++ b/doc/development/swapping_tables.md
@@ -39,14 +39,6 @@ PostgreSQL you can use the `reset_pk_sequence!` method like so:
 reset_pk_sequence!('events')
 ```
 
-For MySQL however you need to do run the following:
-
-```ruby
-amount = Event.pluck('COALESCE(MAX(id), 1)').first
-
-execute "ALTER TABLE events AUTO_INCREMENT = #{amount}"
-```
-
 Failure to reset the primary keys will result in newly created rows starting
 with an ID value of 1. Depending on the existing data this can then lead to
 duplicate key constraints from popping up, preventing users from creating new