diff --git a/lib/mihari/cli/main.rb b/lib/mihari/cli/main.rb
index 6b21c99e..bbff22c9 100644
--- a/lib/mihari/cli/main.rb
+++ b/lib/mihari/cli/main.rb
@@ -21,7 +21,7 @@ class Main < Base
       include Mihari::Commands::Version
       include Mihari::Commands::Web
 
-      desc "database", "Sub commands for database"
+      desc "db", "Sub commands for DB"
       subcommand "db", Database
 
       desc "rule", "Sub commands for rule"
diff --git a/lib/mihari/commands/database.rb b/lib/mihari/commands/database.rb
index bacba298..d70e1a91 100644
--- a/lib/mihari/commands/database.rb
+++ b/lib/mihari/commands/database.rb
@@ -9,6 +9,10 @@ def self.included(thor)
         thor.class_eval do
           desc "migrate", "Migrate DB schemas"
           method_option :verbose, type: :boolean, default: true
+          #
+          # @param [String] direction
+          #
+          #
           def migrate(direction = "up")
             verbose = options["verbose"]
             ActiveRecord::Migration.verbose = verbose
diff --git a/lib/mihari/commands/searcher.rb b/lib/mihari/commands/searcher.rb
index c617dd3c..93c3e0ce 100644
--- a/lib/mihari/commands/searcher.rb
+++ b/lib/mihari/commands/searcher.rb
@@ -10,6 +10,11 @@ def self.included(thor)
         thor.class_eval do
           desc "search [PATH]", "Search by a rule"
           method_option :force_overwrite, type: :boolean, aliases: "-f", desc: "Force an overwrite the rule"
+          #
+          # Search by a rule
+          #
+          # @param [String] path_or_id
+          #
           def search(path_or_id)
             with_db_connection do
               rule = Structs::Rule.from_path_or_id path_or_id
diff --git a/lib/mihari/database.rb b/lib/mihari/database.rb
index 4ca06d97..f219af05 100644
--- a/lib/mihari/database.rb
+++ b/lib/mihari/database.rb
@@ -117,18 +117,23 @@ def adapter
   "sqlite3"
 end
 
+#
+# @return [Array<ActiveRecord::Migration>] schemas
+#
+def schemas
+  [V5Schema]
+end
+
 module Mihari
   class Database
     class << self
-      include Memist::Memoizable
-
       #
       # DB migraration
       #
       # @param [Symbol] direction
       #
       def migrate(direction)
-        [V5Schema].each { |schema| schema.migrate direction }
+        schemas.each { |schema| schema.migrate direction }
       end
 
       #
diff --git a/lib/mihari/mixins/database.rb b/lib/mihari/mixins/database.rb
index 4683d303..e7c02e3b 100644
--- a/lib/mihari/mixins/database.rb
+++ b/lib/mihari/mixins/database.rb
@@ -6,6 +6,8 @@ module Database
       def with_db_connection
         Mihari::Database.connect
         yield
+      rescue ActiveRecord::StatementInvalid
+        Mihari.logger.error("You haven't finished the DB migration! Please run 'mihari db migrate'.")
       ensure
         Mihari::Database.close
       end