Foreign Key Support Fixes #375.

Author: metaskills

CHANGELOG.md

@@ -8,6 +8,7 @@
 * New `SQLServer::Utils::Name` object for decomposing and quoting SQL Server names/identifiers.
 * Support for most all SQL Server types in schema statements and dumping.
 * Support create table with query from relation or select statement.
+* Foreign Key Support Fixes #375.
 
 #### Changed
 

lib/active_record/connection_adapters/sqlserver/schema_creation.rb

@@ -34,6 +34,18 @@ def add_column_options!(sql, options)
           end
         end
 
+        def action_sql(action, dependency)
+          case dependency
+          when :restrict
+            raise ArgumentError, <<-MSG.strip_heredoc
+              '#{dependency}' is not supported for :on_update or :on_delete.
+              Supported values are: :nullify, :cascade
+            MSG
+          else
+            super
+          end
+        end
+
       end
     end
   end

lib/active_record/connection_adapters/sqlserver/schema_statements.rb

@@ -116,6 +116,30 @@ def remove_index!(table_name, index_name)
           do_execute "DROP INDEX #{quote_column_name(index_name)} ON #{quote_table_name(table_name)}"
         end
 
+        def foreign_keys(table_name)
+          identifier = SQLServer::Utils.extract_identifiers(table_name)
+          fk_info = execute_procedure :sp_fkeys, nil, identifier.schema, nil, identifier.object, identifier.schema
+          fk_info.map do |row|
+            from_table = identifier.object
+            to_table = row['PKTABLE_NAME']
+            options = {
+              name: row['FK_NAME'],
+              column: row['FKCOLUMN_NAME'],
+              primary_key: row['PKCOLUMN_NAME'],
+              on_update: extract_foreign_key_action('update', row['FK_NAME']),
+              on_delete: extract_foreign_key_action('delete', row['FK_NAME'])
+            }
+            ForeignKeyDefinition.new from_table, to_table, options
+          end
+        end
+
+        def extract_foreign_key_action(action, fk_name)
+          case select_value("SELECT #{action}_referential_action_desc FROM sys.foreign_keys WHERE name = '#{fk_name}'")
+          when 'CASCADE' then :cascade
+          when 'SET_NULL' then :nullify
+          end
+        end
+
         def type_to_sql(type, limit = nil, precision = nil, scale = nil)
           type_limitable = %w(string integer float char nchar varchar nvarchar).include?(type.to_s)
           limit = nil unless type_limitable

lib/active_record/connection_adapters/sqlserver_adapter.rb

@@ -111,6 +111,10 @@ def supports_views?
         true
       end
 
+      def supports_foreign_keys?
+        true
+      end
+
       def disable_referential_integrity
         do_execute "EXEC sp_MSforeachtable 'ALTER TABLE ? NOCHECK CONSTRAINT ALL'"
         yield

test/cases/coerced_tests.rb

@@ -126,6 +126,13 @@ class ChangeSchemaTest < ActiveRecord::TestCase
       coerce_tests! :test_create_table_with_bigint,
                     :test_create_table_with_defaults
 
+
+    end
+    class ChangeSchemaWithDependentObjectsTest < ActiveRecord::TestCase
+
+      # In SQL Server you have to delete the tables yourself in the right order.
+      coerce_tests! :test_create_table_with_force_cascade_drops_dependent_objects
+
     end
   end
 end
@@ -302,6 +309,28 @@ def test_take_and_first_and_last_with_integer_should_use_sql_limit_coerced
 
 
 
+module ActiveRecord
+  class Migration
+    class ForeignKeyTest < ActiveRecord::TestCase
+
+      # We do not support :restrict.
+      coerce_tests! :test_add_on_delete_restrict_foreign_key
+      def test_add_on_delete_restrict_foreign_key_coerced
+        assert_raises ArgumentError do
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :restrict
+        end
+        assert_raises ArgumentError do
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :restrict
+        end
+      end
+
+    end
+  end
+end
+
+
+
+
 class HasOneAssociationsTest < ActiveRecord::TestCase
 
   # We use OFFSET/FETCH vs TOP. So we always have an order.