diff --git a/config/database.yml.docker b/config/database.yml.docker
deleted file mode 100644
index 60ef8947..00000000
--- a/config/database.yml.docker
+++ /dev/null
@@ -1,7 +0,0 @@
-production:
-  adapter: mysql2
-  host: <%= ENV['DATABASE_HOST'] %>
-  port: <%= ENV['DATABASE_PORT'] %>
-  username: <%= ENV['MYSQL_USER'] %>
-  password: <%= ENV['MYSQL_PASSWORD'] %>
-  database: <%= ENV['MYSQL_DATABASE'] %>
diff --git a/config/database.yml.example b/config/database.yml.example
index f47361d5..dd8ac693 100644
--- a/config/database.yml.example
+++ b/config/database.yml.example
@@ -1,54 +1,32 @@
-# SQLite version 3.x
-#   gem install sqlite3
-#
-#   Ensure the SQLite 3 gem is defined in your Gemfile
-#   gem 'sqlite3'
-development:
-  adapter: sqlite3
-  database: db/development.sqlite3
+<%
+  encoding = 'unicode'
+  if ENV['OSEM_DB_ADAPTER'] == 'mysql2'
+    encoding = 'utf8'
+  end
+%>
+
+
+default: &default
+  adapter: <%= ENV['OSEM_DB_ADAPTER'] || 'postgresql' %>
+  encoding: <%= encoding %>
+  host: <%= ENV['OSEM_DB_HOST'] || 'database' %>
+  port: <%= ENV['OSEM_DB_PORT'] || '5432'  %>
+  username: <%= ENV['OSEM_DB_USER'] || 'postgres' %>
+  password: <%= ENV['OSEM_DB_PASSWORD'] || 'mysecretpassword' %>
+  database: <%= ENV['OSEM_DB_NAME'] || 'postgres' %>
   pool: 5
   timeout: 5000
 
-## PostgreSQL
-##   gem install pg
-## 
-##   Ensure the postgres gem is defined in your Gemfile
-##   gem 'pg'
-##   Update with your database name and login credentials
-# development:
-#   adapter: postgresql
-#   encoding: unicode
-#   database: database_name
-#   pool: 5
-#   username: username
-#   password: password
-
-## MySQL
-##   gem install mysql2
-##
-##   Ensure the mysql gem is defined in your Gemfile
-##   gem 'mysql2'
-##   Update with your database name and login credentials
-# development:
-#   adapter: mysql2
-#   encoding: utf8
-#   database: database_name
-#   pool: 5
-#   username: username
-#   password: password
-#   socket: /tmp/mysql.sock
+development:
+  <<: *default
+  database: osem_development
 
 # Warning: The database defined as "test" will be erased and
-# re-generated from your development database when you run "rake".
+# re-generated when you run "rake".
 # Do not set this db to the same as development or production.
 test:
-  adapter: sqlite3
-  database: db/test.sqlite3
-  pool: 5
-  timeout: 5000
+  <<: *default
+  database: osem_test
 
 production:
-  adapter: sqlite3
-  database: db/production.sqlite3
-  pool: 5
-  timeout: 5000
+  <<: *default
diff --git a/config/database.yml.heroku b/config/database.yml.heroku
deleted file mode 100644
index f0886077..00000000
--- a/config/database.yml.heroku
+++ /dev/null
@@ -1,2 +0,0 @@
-production:
-  url: <%= ENV["CLEARDB_DATABASE_URL"].sub(/^mysql/, "mysql2") %>
diff --git a/config/database.yml.travis b/config/database.yml.travis
deleted file mode 100644
index c0410217..00000000
--- a/config/database.yml.travis
+++ /dev/null
@@ -1,5 +0,0 @@
-test:
-  adapter: mysql2
-  database: osem_test
-  username: root
-  encoding: utf8