diff --git a/packages/forest_admin_datasource_active_record/Gemfile b/packages/forest_admin_datasource_active_record/Gemfile
index fcb660e5c..89f105034 100644
--- a/packages/forest_admin_datasource_active_record/Gemfile
+++ b/packages/forest_admin_datasource_active_record/Gemfile
@@ -4,6 +4,8 @@ source "https://rubygems.org"
 gemspec
 
 gem 'database_cleaner-active_record'
+gem 'forest_admin_agent'
+gem 'forest_admin_datasource_customizer'
 gem 'forest_admin_datasource_toolkit'
 gem 'rake', '~> 13.0'
 gem 'rubocop', '~> 1.21'
diff --git a/packages/forest_admin_datasource_active_record/Gemfile-test b/packages/forest_admin_datasource_active_record/Gemfile-test
index b9c65ad44..f4fbb646e 100644
--- a/packages/forest_admin_datasource_active_record/Gemfile-test
+++ b/packages/forest_admin_datasource_active_record/Gemfile-test
@@ -9,6 +9,8 @@ gem 'rubocop', '~> 1.21'
 group :development, :test do
   gem 'database_cleaner-active_record'
   gem 'forest_admin_datasource_toolkit', path: '../forest_admin_datasource_toolkit'
+  gem 'forest_admin_datasource_customizer', path: '../forest_admin_datasource_customizer'
+  gem 'forest_admin_agent', path: '../forest_admin_agent'
   gem 'rails'
   gem 'rspec-rails', '~> 3.0'
   gem 'simplecov', '~> 0.22', require: false
diff --git a/packages/forest_admin_datasource_active_record/lib/forest_admin_datasource_active_record/parser/column.rb b/packages/forest_admin_datasource_active_record/lib/forest_admin_datasource_active_record/parser/column.rb
index e578c6173..be31b6a77 100644
--- a/packages/forest_admin_datasource_active_record/lib/forest_admin_datasource_active_record/parser/column.rb
+++ b/packages/forest_admin_datasource_active_record/lib/forest_admin_datasource_active_record/parser/column.rb
@@ -27,8 +27,18 @@ def get_column_type(model, column)
           return 'Enum'
         end
 
+        if TYPES.key?(column.type)
+          type = TYPES[column.type]
+        else
+          type = TYPES[:string]
+          ForestAdminAgent::Facades::Container.logger.log(
+            'Info',
+            "unknown type '#{column.type}' for field named '#{column.name}', '#{TYPES[:string]}' type use by default"
+          )
+        end
+
         is_array = column.respond_to?(:array) && column.array == true
-        is_array ? "[#{TYPES[column.type]}]" : TYPES[column.type]
+        is_array ? "[#{type}]" : type
       end
 
       def get_enum_values(model, column)
diff --git a/packages/forest_admin_datasource_active_record/lib/forest_admin_datasource_active_record/parser/validation.rb b/packages/forest_admin_datasource_active_record/lib/forest_admin_datasource_active_record/parser/validation.rb
index cb65efa24..b8949c592 100644
--- a/packages/forest_admin_datasource_active_record/lib/forest_admin_datasource_active_record/parser/validation.rb
+++ b/packages/forest_admin_datasource_active_record/lib/forest_admin_datasource_active_record/parser/validation.rb
@@ -51,7 +51,7 @@ def parse_numericality_validator(validator, parsed_validations)
       end
 
       def parse_length_validator(validator, parsed_validations)
-        return unless get_column_type(column) == 'String'
+        return unless get_column_type(@model, column) == 'String'
 
         validator.options.each do |option, value|
           case option
diff --git a/packages/forest_admin_datasource_active_record/spec/lib/forest_admin_datasource_active_record/parser/column_spec.rb b/packages/forest_admin_datasource_active_record/spec/lib/forest_admin_datasource_active_record/parser/column_spec.rb
index 522771c6c..abdbccbcf 100644
--- a/packages/forest_admin_datasource_active_record/spec/lib/forest_admin_datasource_active_record/parser/column_spec.rb
+++ b/packages/forest_admin_datasource_active_record/spec/lib/forest_admin_datasource_active_record/parser/column_spec.rb
@@ -19,6 +19,18 @@ module Parser
         it { expect(dummy_class.get_column_type(User, columns['time_field'])).to eq 'Time' }
         it { expect(dummy_class.get_column_type(User, columns['binary_field'])).to eq 'Binary' }
         it { expect(dummy_class.get_column_type(User, columns['enum_field'])).to eq 'Enum' }
+
+        it 'return string type by default when column type is unknown' do
+          logger = instance_double(Logger, log: nil)
+          allow(ForestAdminAgent::Facades::Container).to receive(:logger).and_return(logger)
+          column = instance_double(
+            ActiveRecord::ConnectionAdapters::SQLite3::Column,
+            name: 'foo',
+            type: 'unknown type'
+          )
+
+          expect(dummy_class.get_column_type(User, column)).to eq 'String'
+        end
       end
 
       describe 'get_enum_values' do