Make to primary key instead of an unique index for internal tables

4 files changed, 5 insertions, 40 deletions

diff --git a/activerecord/lib/active_record/internal_metadata.rb b/activerecord/lib/active_record/internal_metadata.rb
index 10fee4dca2..641b137851 100644
--- a/activerecord/lib/active_record/internal_metadata.rb
+++ b/activerecord/lib/active_record/internal_metadata.rb
@@ -18,10 +18,6 @@ module ActiveRecord
         "#{table_name_prefix}#{ActiveRecord::Base.internal_metadata_table_name}#{table_name_suffix}"
       end
 
-      def index_name
-        "#{table_name_prefix}unique_#{ActiveRecord::Base.internal_metadata_table_name}#{table_name_suffix}"
-      end
-
       def []=(key, value)
         first_or_initialize(key: key).update_attributes!(value: value)
       end
@@ -38,10 +34,8 @@ module ActiveRecord
       def create_table
         unless table_exists?
           connection.create_table(table_name, id: false) do |t|
-            t.column :key,   :string, null: false, limit: KEY_LIMIT
-            t.column :value, :string
-            t.index  :key, unique: true, name: index_name
-
+            t.string :key, primary_key: true, limit: KEY_LIMIT
+            t.string :value
             t.timestamps
           end
         end
diff --git a/activerecord/lib/active_record/schema_migration.rb b/activerecord/lib/active_record/schema_migration.rb
index 8f0ab2b55b..a5b693c349 100644
--- a/activerecord/lib/active_record/schema_migration.rb
+++ b/activerecord/lib/active_record/schema_migration.rb
@@ -16,22 +16,17 @@ module ActiveRecord
         "#{table_name_prefix}#{ActiveRecord::Base.schema_migrations_table_name}#{table_name_suffix}"
       end
 
-      def index_name
-        "#{table_name_prefix}unique_#{ActiveRecord::Base.schema_migrations_table_name}#{table_name_suffix}"
-      end
-
       def table_exists?
         ActiveSupport::Deprecation.silence { connection.table_exists?(table_name) }
       end
 
       def create_table(limit=nil)
         unless table_exists?
-          version_options = {null: false}
+          version_options = { primary_key: true }
           version_options[:limit] = limit if limit
 
           connection.create_table(table_name, id: false) do |t|
-            t.column :version, :string, version_options
-            t.index  :version, unique: true, name: index_name
+            t.string :version, version_options
           end
         end
       end
diff --git a/activerecord/test/cases/ar_schema_test.rb b/activerecord/test/cases/ar_schema_test.rb
index 1f32c48b95..9c99689c1e 100644
--- a/activerecord/test/cases/ar_schema_test.rb
+++ b/activerecord/test/cases/ar_schema_test.rb
@@ -21,7 +21,7 @@ if ActiveRecord::Base.connection.supports_migrations?
       ActiveRecord::Migration.verbose = @original_verbose
     end
 
-    def test_has_has_primary_key
+    def test_has_primary_key
       old_primary_key_prefix_type = ActiveRecord::Base.primary_key_prefix_type
       ActiveRecord::Base.primary_key_prefix_type = :table_name_with_underscore
       assert_equal "version", ActiveRecord::SchemaMigration.primary_key
diff --git a/activerecord/test/cases/migration/table_and_index_test.rb b/activerecord/test/cases/migration/table_and_index_test.rb
deleted file mode 100644
index 24cba84a09..0000000000
--- a/activerecord/test/cases/migration/table_and_index_test.rb
+++ /dev/null
@@ -1,24 +0,0 @@
-require "cases/helper"
-
-module ActiveRecord
-  class Migration
-    class TableAndIndexTest < ActiveRecord::TestCase
-      def test_add_schema_info_respects_prefix_and_suffix
-        conn = ActiveRecord::Base.connection
-
-        conn.drop_table(ActiveRecord::Migrator.schema_migrations_table_name, if_exists: true)
-        # Use shorter prefix and suffix as in Oracle database identifier cannot be larger than 30 characters
-        ActiveRecord::Base.table_name_prefix = 'p_'
-        ActiveRecord::Base.table_name_suffix = '_s'
-        conn.drop_table(ActiveRecord::Migrator.schema_migrations_table_name, if_exists: true)
-
-        conn.initialize_schema_migrations_table
-
-        assert_equal "p_unique_schema_migrations_s", conn.indexes(ActiveRecord::Migrator.schema_migrations_table_name)[0][:name]
-      ensure
-        ActiveRecord::Base.table_name_prefix = ""
-        ActiveRecord::Base.table_name_suffix = ""
-      end
-    end
-  end
-end