Add MySQL info in install requirements

doc/install/database_mysql.md

 # Database MySQL
 
-## Note
-
-We do not recommend using MySQL due to various issues. For example, case [(in)sensitivity](https://dev.mysql.com/doc/refman/5.0/en/case-sensitivity.html) and [problems](https://bugs.mysql.com/bug.php?id=65830) that [suggested](https://bugs.mysql.com/bug.php?id=50909) [fixes](https://bugs.mysql.com/bug.php?id=65830) [have](https://bugs.mysql.com/bug.php?id=63164).
+>**Note:**
+We do not recommend using MySQL due to various issues. For example, case
+[(in)sensitivity](https://dev.mysql.com/doc/refman/5.0/en/case-sensitivity.html)
+and [problems](https://bugs.mysql.com/bug.php?id=65830) that
+[suggested](https://bugs.mysql.com/bug.php?id=50909)
+[fixes](https://bugs.mysql.com/bug.php?id=65830) [have](https://bugs.mysql.com/bug.php?id=63164).
 
 ## Initial database setup
 
-    # Install the database packages
-    sudo apt-get install -y mysql-server mysql-client libmysqlclient-dev
-
-    # Ensure you have MySQL version 5.5.14 or later
-    mysql --version
+```
+# Install the database packages
+sudo apt-get install -y mysql-server mysql-client libmysqlclient-dev
 
-    # Pick a MySQL root password (can be anything), type it and press enter
-    # Retype the MySQL root password and press enter
+# Ensure you have MySQL version 5.5.14 or later
+mysql --version
 
-    # Secure your installation
-    sudo mysql_secure_installation
+# Pick a MySQL root password (can be anything), type it and press enter
+# Retype the MySQL root password and press enter
 
-    # Login to MySQL
-    mysql -u root -p
+# Secure your installation
+sudo mysql_secure_installation
 
-    # Type the MySQL root password
+# Login to MySQL
+mysql -u root -p
 
-    # Create a user for GitLab
-    # do not type the 'mysql>', this is part of the prompt
-    # change $password in the command below to a real password you pick
-    mysql> CREATE USER 'git'@'localhost' IDENTIFIED BY '$password';
+# Type the MySQL root password
 
-    # Ensure you can use the InnoDB engine which is necessary to support long indexes
-    # If this fails, check your MySQL config files (e.g. `/etc/mysql/*.cnf`, `/etc/mysql/conf.d/*`) for the setting "innodb = off"
-    mysql> SET storage_engine=INNODB;
+# Create a user for GitLab
+# do not type the 'mysql>', this is part of the prompt
+# change $password in the command below to a real password you pick
+mysql> CREATE USER 'git'@'localhost' IDENTIFIED BY '$password';
 
-    # If you have MySQL < 5.7.7 and want to enable utf8mb4 character set support with your GitLab install, you must set the following NOW:
-    mysql> SET GLOBAL innodb_file_per_table=1, innodb_file_format=Barracuda, innodb_large_prefix=1;
+# Ensure you can use the InnoDB engine which is necessary to support long indexes
+# If this fails, check your MySQL config files (e.g. `/etc/mysql/*.cnf`, `/etc/mysql/conf.d/*`) for the setting "innodb = off"
+mysql> SET storage_engine=INNODB;
 
-    # Create the GitLab production database
-    mysql> CREATE DATABASE IF NOT EXISTS `gitlabhq_production` DEFAULT CHARACTER SET `utf8` COLLATE `utf8_general_ci`;
+# If you have MySQL < 5.7.7 and want to enable utf8mb4 character set support with your GitLab install, you must set the following NOW:
+mysql> SET GLOBAL innodb_file_per_table=1, innodb_file_format=Barracuda, innodb_large_prefix=1;
 
-    # Grant the GitLab user necessary permissions on the database
-    mysql> GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, CREATE TEMPORARY TABLES, DROP, INDEX, ALTER, LOCK TABLES, REFERENCES ON `gitlabhq_production`.* TO 'git'@'localhost';
+# Create the GitLab production database
+mysql> CREATE DATABASE IF NOT EXISTS `gitlabhq_production` DEFAULT CHARACTER SET `utf8` COLLATE `utf8_general_ci`;
 
-    # Quit the database session
-    mysql> \q
+# Grant the GitLab user necessary permissions on the database
+mysql> GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, CREATE TEMPORARY TABLES, DROP, INDEX, ALTER, LOCK TABLES, REFERENCES ON `gitlabhq_production`.* TO 'git'@'localhost';
 
-    # Try connecting to the new database with the new user
-    sudo -u git -H mysql -u git -p -D gitlabhq_production
+# Quit the database session
+mysql> \q
 
-    # Type the password you replaced $password with earlier
+# Try connecting to the new database with the new user
+sudo -u git -H mysql -u git -p -D gitlabhq_production
 
-    # You should now see a 'mysql>' prompt
+# Type the password you replaced $password with earlier
 
-    # Quit the database session
-    mysql> \q
+# You should now see a 'mysql>' prompt
 
-    # You are done installing the database for now and can go back to the rest of the installation.
+# Quit the database session
+mysql> \q
+```
 
+You are done installing the database for now and can go back to the rest of the installation.
 Please proceed to the rest of the installation before running through the utf8mb4 support section.
 
-
 ### MySQL utf8mb4 support
 
 After installation or upgrade, remember to [convert any new tables](#convert) to `utf8mb4`/`utf8mb4_general_ci`.

doc/install/requirements.md

@@ -15,11 +15,11 @@ For the installations options please see [the installation page on the GitLab we
 
 ### Unsupported Unix distributions
 
-- OS X
 - Arch Linux
 - Fedora
-- Gentoo
 - FreeBSD
+- Gentoo
+- macOS
 
 On the above unsupported distributions is still possible to install GitLab yourself.
 Please see the [installation from source guide](installation.md) and the [installation guides](https://about.gitlab.com/installation/) for more information.
@@ -120,7 +120,12 @@ To change the Unicorn workers when you have the Omnibus package please see [the
 
 ## Database
 
-If you want to run the database separately expect a size of about 1 MB per user.
+We currently support the following databases:
+
+- PostgreSQL (recommended)
+- MySQL/MariaDB
+
+If you want to run the database separately, expect a size of about 1 MB per user.
 
 ### PostgreSQL Requirements
 
@@ -128,7 +133,9 @@ Users using PostgreSQL must ensure the `pg_trgm` extension is loaded into every
 GitLab database. This extension can be enabled (using a PostgreSQL super user)
 by running the following query for every database:
 
-    CREATE EXTENSION pg_trgm;
+```
+CREATE EXTENSION pg_trgm;
+```
 
 On some systems you may need to install an additional package (e.g.
 `postgresql-contrib`) for this extension to become available.