MySQL: Check error number instead of a message

To be able to check regardless of locale.

activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb

@@ -8,6 +8,8 @@ require "mysql2"
 
 module ActiveRecord
   module ConnectionHandling # :nodoc:
+    ER_BAD_DB_ERROR = 1049
+
     # Establishes a connection to the database that's used by all Active Record objects.
     def mysql2_connection(config)
       config = config.symbolize_keys
@@ -22,7 +24,7 @@ module ActiveRecord
       client = Mysql2::Client.new(config)
       ConnectionAdapters::Mysql2Adapter.new(client, logger, nil, config)
     rescue Mysql2::Error => error
-      if error.message.include?("Unknown database")
+      if error.error_number == ER_BAD_DB_ERROR
         raise ActiveRecord::NoDatabaseError
       else
         raise

activerecord/lib/active_record/tasks/mysql_database_tasks.rb

@@ -3,6 +3,8 @@
 module ActiveRecord
   module Tasks # :nodoc:
     class MySQLDatabaseTasks # :nodoc:
+      ER_DB_CREATE_EXISTS = 1007
+
       delegate :connection, :establish_connection, to: ActiveRecord::Base
 
       def initialize(configuration)
@@ -14,7 +16,7 @@ module ActiveRecord
         connection.create_database configuration["database"], creation_options
         establish_connection configuration
       rescue ActiveRecord::StatementInvalid => error
-        if error.message.include?("database exists")
+        if error.cause.error_number == ER_DB_CREATE_EXISTS
           raise DatabaseAlreadyExists
         else
           raise