diff --git a/activerecord/lib/active_record/database_configurations.rb b/activerecord/lib/active_record/database_configurations.rb
index 4656045fe5..7431a1c759 100644
--- a/activerecord/lib/active_record/database_configurations.rb
+++ b/activerecord/lib/active_record/database_configurations.rb
@@ -17,22 +17,22 @@ module ActiveRecord
     end
 
     # Collects the configs for the environment and optionally the specification
-    # name passed in. To include replica configurations pass `include_replicas: true`.
+    # name passed in. To include replica configurations pass <tt>include_replicas: true</tt>.
     #
     # If a spec name is provided a single DatabaseConfig object will be
     # returned, otherwise an array of DatabaseConfig objects will be
     # returned that corresponds with the environment and type requested.
     #
-    # Options:
+    # ==== Options
     #
-    # <tt>env_name:</tt> The environment name. Defaults to +nil+ which will collect
-    # configs for all environments.
-    # <tt>spec_name:</tt> The specification name (i.e. primary, animals, etc.). Defaults
-    # to +nil+.
-    # <tt>include_replicas:</tt> Determines whether to include replicas in
-    # the returned list. Most of the time we're only iterating over the write
-    # connection (i.e. migrations don't need to run for the write and read connection).
-    # Defaults to +false+.
+    # * <tt>env_name:</tt> The environment name. Defaults to +nil+ which will collect
+    #   configs for all environments.
+    # * <tt>spec_name:</tt> The specification name (i.e. primary, animals, etc.). Defaults
+    #   to +nil+.
+    # * <tt>include_replicas:</tt> Determines whether to include replicas in
+    #   the returned list. Most of the time we're only iterating over the write
+    #   connection (i.e. migrations don't need to run for the write and read connection).
+    #   Defaults to +false+.
     def configs_for(env_name: nil, spec_name: nil, include_replicas: false)
       configs = env_with_configs(env_name)
 
@@ -53,7 +53,7 @@ module ActiveRecord
 
     # Returns the config hash that corresponds with the environment
     #
-    # If the application has multiple databases `default_hash` will
+    # If the application has multiple databases +default_hash+ will
     # return the first config hash for the environment.
     #
     #   { database: "my_db", adapter: "mysql2" }
@@ -65,7 +65,7 @@ module ActiveRecord
 
     # Returns a single DatabaseConfig object based on the requested environment.
     #
-    # If the application has multiple databases `find_db_config` will return
+    # If the application has multiple databases +find_db_config+ will return
     # the first DatabaseConfig for the environment.
     def find_db_config(env)
       configurations.find do |db_config|
diff --git a/activerecord/lib/active_record/database_configurations/hash_config.rb b/activerecord/lib/active_record/database_configurations/hash_config.rb
index 574cb6bf15..e31ff09391 100644
--- a/activerecord/lib/active_record/database_configurations/hash_config.rb
+++ b/activerecord/lib/active_record/database_configurations/hash_config.rb
@@ -14,16 +14,16 @@ module ActiveRecord
     #   #<ActiveRecord::DatabaseConfigurations::HashConfig:0x00007fd1acbded10
     #     @env_name="development", @spec_name="primary", @config={"database"=>"db_name"}>
     #
-    # Options are:
+    # ==== Options
     #
-    # <tt>:env_name</tt> - The Rails environment, i.e. "development"
-    # <tt>:spec_name</tt> - The specification name. In a standard two-tier
-    # database configuration this will default to "primary". In a multiple
-    # database three-tier database configuration this corresponds to the name
-    # used in the second tier, for example "primary_readonly".
-    # <tt>:config</tt> - The config hash. This is the hash that contains the
-    # database adapter, name, and other important information for database
-    # connections.
+    # * <tt>:env_name</tt> - The Rails environment, i.e. "development".
+    # * <tt>:spec_name</tt> - The specification name. In a standard two-tier
+    #   database configuration this will default to "primary". In a multiple
+    #   database three-tier database configuration this corresponds to the name
+    #   used in the second tier, for example "primary_readonly".
+    # * <tt>:config</tt> - The config hash. This is the hash that contains the
+    #   database adapter, name, and other important information for database
+    #   connections.
     class HashConfig < DatabaseConfig
       attr_reader :config
 
@@ -33,14 +33,14 @@ module ActiveRecord
       end
 
       # Determines whether a database configuration is for a replica / readonly
-      # connection. If the `replica` key is present in the config, `replica?` will
+      # connection. If the +replica+ key is present in the config, +replica?+ will
       # return +true+.
       def replica?
         config["replica"]
       end
 
       # The migrations paths for a database configuration. If the
-      # `migrations_paths` key is present in the config, `migrations_paths`
+      # +migrations_paths+ key is present in the config, +migrations_paths+
       # will return its value.
       def migrations_paths
         config["migrations_paths"]
diff --git a/activerecord/lib/active_record/database_configurations/url_config.rb b/activerecord/lib/active_record/database_configurations/url_config.rb
index 8e8aa69478..e2d30ae416 100644
--- a/activerecord/lib/active_record/database_configurations/url_config.rb
+++ b/activerecord/lib/active_record/database_configurations/url_config.rb
@@ -17,17 +17,17 @@ module ActiveRecord
     #     @config={"adapter"=>"postgresql", "database"=>"foo", "host"=>"localhost"},
     #     @url="postgres://localhost/foo">
     #
-    # Options are:
+    # ==== Options
     #
-    # <tt>:env_name</tt> - The Rails environment, ie "development"
-    # <tt>:spec_name</tt> - The specification name. In a standard two-tier
-    # database configuration this will default to "primary". In a multiple
-    # database three-tier database configuration this corresponds to the name
-    # used in the second tier, for example "primary_readonly".
-    # <tt>:url</tt> - The database URL.
-    # <tt>:config</tt> - The config hash. This is the hash that contains the
-    # database adapter, name, and other important information for database
-    # connections.
+    # * <tt>:env_name</tt> - The Rails environment, ie "development".
+    # * <tt>:spec_name</tt> - The specification name. In a standard two-tier
+    #   database configuration this will default to "primary". In a multiple
+    #   database three-tier database configuration this corresponds to the name
+    #   used in the second tier, for example "primary_readonly".
+    # * <tt>:url</tt> - The database URL.
+    # * <tt>:config</tt> - The config hash. This is the hash that contains the
+    #   database adapter, name, and other important information for database
+    #   connections.
     class UrlConfig < DatabaseConfig
       attr_reader :url, :config
 
@@ -42,14 +42,14 @@ module ActiveRecord
       end
 
       # Determines whether a database configuration is for a replica / readonly
-      # connection. If the `replica` key is present in the config, `replica?` will
+      # connection. If the +replica+ key is present in the config, +replica?+ will
       # return +true+.
       def replica?
         config["replica"]
       end
 
       # The migrations paths for a database configuration. If the
-      # `migrations_paths` key is present in the config, `migrations_paths`
+      # +migrations_paths+ key is present in the config, +migrations_paths+
       # will return its value.
       def migrations_paths
         config["migrations_paths"]