Add support for #disable_referential_integrity block.

Author: metaskills

lib/active_record/connection_adapters/sqlserver_adapter.rb

@@ -364,10 +364,14 @@ def quoted_date(value)
         end
       end
 
-      
       # REFERENTIAL INTEGRITY ====================================#
-      # TODO: Add #disable_referential_integrity if we can use it
 
+      def disable_referential_integrity(&block)
+        execute "EXEC sp_MSForEachTable 'ALTER TABLE ? NOCHECK CONSTRAINT ALL'"
+        yield
+      ensure
+        execute "EXEC sp_MSForEachTable 'ALTER TABLE ? CHECK CONSTRAINT ALL'"
+      end
 
       # DATABASE STATEMENTS ======================================
 

test/cases/adapter_test_sqlserver.rb

@@ -189,6 +189,32 @@ def setup
 
   end
 
+  context 'When disableing referential integrity' do
+    
+    setup do
+      @parent = FkTestHasPk.create!
+      @member = FkTestHasFk.create!(:fk_id => @parent.id)
+    end
+    
+    should 'NOT ALLOW by default the deletion of a referenced parent' do
+      assert_raise(ActiveRecord::StatementInvalid) { @parent.destroy }
+    end
+    
+    should 'ALLOW deletion of referenced parent using #disable_referential_integrity block' do
+      assert_nothing_raised(ActiveRecord::StatementInvalid) do
+        FkTestHasPk.connection.disable_referential_integrity { @parent.destroy }
+      end
+    end
+    
+    should 'again NOT ALLOW deletion of referenced parent after #disable_referential_integrity block' do
+      assert_raise(ActiveRecord::StatementInvalid) do
+        FkTestHasPk.connection.disable_referential_integrity { }
+        @parent.destroy
+      end
+    end
+    
+  end
+  
   context 'For DatabaseStatements' do
 
   end

test/cases/sqlserver_helper.rb

@@ -13,6 +13,8 @@
 ActiveRecord::Migration.verbose = false
 
 class TableWithRealColumn < ActiveRecord::Base; end
+class FkTestHasFk < ActiveRecord::Base ; end
+class FkTestHasPk < ActiveRecord::Base ; end
 
 # Change the text database type to support ActiveRecord's tests for = on text columns which 
 # is not supported in SQL Server text columns, so use varchar(8000) instead.

test/schema/sqlserver_specific_schema.rb

@@ -29,4 +29,18 @@
     t.column :string_with_pretend_null_four, :string, :default => '(NULL)'
   end
 
+  
+  create_table :fk_test_has_fks, :force => true do |t|
+    t.integer :fk_id, :null => false
+  end
+  create_table :fk_test_has_pks, :force => true do |t|
+  end
+  execute <<-ADDFKSQL
+    ALTER TABLE fk_test_has_fks 
+    ADD CONSTRAINT FK__fk_test_has_fk_fk_id
+    FOREIGN KEY (#{quote_column_name('fk_id')}) 
+    REFERENCES #{quote_table_name('fk_test_has_pks')} (#{quote_column_name('id')})
+  ADDFKSQL
+  
+  
 end