you can provide uuid_generate_v4 as the default value for uuid columns

2 files changed, 9 insertions, 2 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
index 805832f01e..21dda17f2f 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
@@ -29,6 +29,7 @@ module ActiveRecord
         column_options = {}
         column_options[:null] = null unless null.nil?
         column_options[:default] = default unless default.nil?
+        column_options[:column] = self
         add_column_options!(column_sql, column_options) unless type.to_sym == :primary_key
         column_sql
       end
@@ -36,7 +37,7 @@ module ActiveRecord
       private
 
         def add_column_options!(sql, options)
-          base.add_column_options!(sql, options.merge(:column => self))
+          base.add_column_options!(sql, options)
         end
     end
 
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index eb541b0215..dfa4c3967a 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -632,7 +632,13 @@ module ActiveRecord
         if options[:array] || options[:column].try(:array)
           sql << '[]'
         end
-        super
+
+        column = options.fetch(:column) { return super }
+        if column.type == :uuid && options[:default] =~ /\(\)/
+          sql << " DEFAULT #{options[:default]}"
+        else
+          super
+        end
       end
 
       # Set the authorized user for this session