0
@@ -2,6 +2,8 @@
0
 
0
 * Quote ActiveSupport::Multibyte::Chars.  #6653 [Julian Tarkhanov]
0
 
0
+* MySQL: detect when a NOT NULL column without a default value is misreported as default ''.  Can't detect for string, text, and binary columns since '' is a legitimate default.  #6156 [simon@redhillconsulting.com.au, obrie, Jonathan Viney, Jeremy Kemper]
0
+
0
 * validates_numericality_of uses \A \Z to ensure the entire string matches rather than ^ $ which may match one valid line of a multiline string.  #5716 [Andreas Schwarz]
0
 
0
 * Oracle: automatically detect the primary key.  #6594 [vesaria, Michael Schoen]

0
@@ -1,4 +1,5 @@
0
 require 'active_record/connection_adapters/abstract_adapter'
0
+require 'set'
0
 
0
 module MysqlCompat
0
   # add all_hashes method to standard mysql-c bindings or pure ruby version
0
@@ -84,12 +85,31 @@ module ActiveRecord
0
 
0
   module ConnectionAdapters
0
     class MysqlColumn < Column #:nodoc:
0
+      TYPES_ALLOWING_EMPTY_STRING_DEFAULT = Set.new([:binary, :string, :text])
0
+
0
+      def initialize(name, default, sql_type = nil, null = true)
0
+        @original_default = default
0
+        super
0
+        @default = nil if missing_default_forged_as_empty_string?
0
+      end
0
+
0
       private
0
         def simplified_type(field_type)
0
           return :boolean if MysqlAdapter.emulate_booleans && field_type.downcase.index("tinyint(1)")
0
           return :string  if field_type =~ /enum/i
0
           super
0
         end
0
+
0
+        # MySQL misreports NOT NULL column default when none is given.
0
+        # We can't detect this for columns which may have a legitimate ''
0
+        # default (string, text, binary) but we can for others (integer,
0
+        # datetime, boolean, and the rest).
0
+        #
0
+        # Test whether the column has default '', is not null, and is not
0
+        # a type allowing default ''.
0
+        def missing_default_forged_as_empty_string?
0
+          !null && @original_default == '' && !TYPES_ALLOWING_EMPTY_STRING_DEFAULT.include?(type)
0
+        end
0
     end
0
 
0
     # The MySQL adapter will work with both Ruby/MySQL, which is a Ruby-based MySQL adapter that comes bundled with Active Record, and with

0
@@ -1,8 +1,24 @@
0
 require 'abstract_unit'
0
 require 'fixtures/default'
0
+require 'fixtures/entrant'
0
 
0
-if current_adapter?(:PostgreSQLAdapter, :SQLServerAdapter)
0
-  class DefaultsTest < Test::Unit::TestCase
0
+class DefaultTest < Test::Unit::TestCase
0
+  def test_nil_defaults_for_not_null_columns
0
+    column_defaults =
0
+      if current_adapter?(:MysqlAdapter)
0
+        { 'id' => nil, 'name' => '',  'course_id' => nil }
0
+      else
0
+        { 'id' => nil, 'name' => nil, 'course_id' => nil }
0
+      end
0
+
0
+    column_defaults.each do |name, default|
0
+      column = Entrant.columns_hash[name]
0
+      assert !column.null, "#{name} column should be NOT NULL"
0
+      assert_equal default, column.default, "#{name} column should be DEFAULT #{default.inspect}"
0
+    end
0
+  end
0
+
0
+  if current_adapter?(:PostgreSQLAdapter, :SQLServerAdapter, :FirebirdAdapter, :OpenBaseAdapter)
0
     def test_default_integers
0
       default = Default.new
0
       assert_instance_of Fixnum, default.positive_integer

0
@@ -130,8 +130,8 @@ CREATE TABLE auto_id_tests (
0
 
0
 CREATE TABLE entrants (
0
   id serial,
0
-  name text,
0
-  course_id integer
0
+  name text not null,
0
+  course_id integer not null
0
 );
0
 
0
 CREATE TABLE colnametests (