Do not ues Regexp for ID insert guards. For example:

```ruby
c = Company.connection
c.with_identity_insert_enabled('companies') do
  c.insert "INSERT INTO companies (id, name) VALUES(100, N'Totally happening!')"
end
```

Author: metaskills

CHANGELOG.md

@@ -17,6 +17,7 @@
   * Simple 2012 schmea addition and extensive column/type_cast object tests.
 * Follow Rails convention and remove varying character default limits.
 * The `cs_equality_operator` is now s class configuration property only.
+* The `with_identity_insert_enabled(table_name)` is now public.
 
 #### Deprecated
 
@@ -38,6 +39,7 @@
   * edition
 * Removed tests for old issue #164. Handled by core types now.
 * The `activity_stats` method. Please put this in a gem if needed.
+* We no longger use regular expressions to fix identity inserts. Use ActiveRecord or public ID insert helper.
 
 #### Fixed
 

lib/active_record/connection_adapters/sqlserver/database_statements.rb

@@ -16,19 +16,22 @@ def execute(sql, name = nil)
         end
 
         def exec_query(sql, name = 'SQL', binds = [], sqlserver_options = {})
-          if id_insert_table_name = sqlserver_options[:insert] ? query_requires_identity_insert?(sql) : nil
-            with_identity_insert_enabled(id_insert_table_name) { do_exec_query(sql, name, binds) }
-          elsif update_sql?(sql)
+          if update_sql?(sql)
             sql = strip_ident_from_update(sql)
             do_exec_query(sql, name, binds)
           else
             do_exec_query(sql, name, binds)
           end
         end
 
-        # The abstract adapter ignores the last two parameters also
         def exec_insert(sql, name, binds, _pk = nil, _sequence_name = nil)
-          exec_query sql, name, binds, insert: true
+          id_insert = binds_have_identity_column?(binds)
+          id_table  = table_name_from_binds(binds) if id_insert
+          if id_insert && id_table
+            with_identity_insert_enabled(id_table) { exec_query(sql, name, binds) }
+          else
+            exec_query(sql, name, binds)
+          end
         end
 
         def exec_delete(sql, name, binds)
@@ -110,6 +113,14 @@ def execute_procedure(proc_name, *variables)
           end
         end
 
+        def with_identity_insert_enabled(table_name)
+          table_name = quote_table_name(table_name_or_views_table_name(table_name))
+          set_identity_insert(table_name, true)
+          yield
+        ensure
+          set_identity_insert(table_name, false)
+        end
+
         def use_database(database = nil)
           return if sqlserver_azure?
           name = SQLServer::Utils.extract_identifiers(database || @connection_options[:database]).quoted
@@ -269,6 +280,26 @@ def sql_for_insert(sql, pk, id_value, sequence_name, binds)
 
         # === SQLServer Specific ======================================== #
 
+        def binds_have_identity_column?(binds)
+          binds.any? do |column_value|
+            column, value = column_value
+            SQLServerColumn === column && column.is_identity?
+          end
+        end
+
+        def table_name_from_binds(binds)
+          binds.detect { |column_value|
+            column, value = column_value
+            SQLServerColumn === column
+          }.try(:first).try(:table_name)
+        end
+
+        def set_identity_insert(table_name, enable = true)
+          do_execute "SET IDENTITY_INSERT #{table_name} #{enable ? 'ON' : 'OFF'}"
+        rescue Exception
+          raise ActiveRecordError, "IDENTITY_INSERT could not be turned #{enable ? 'ON' : 'OFF'} for table #{table_name}"
+        end
+
         def valid_isolation_levels
           ['READ COMMITTED', 'READ UNCOMMITTED', 'REPEATABLE READ', 'SERIALIZABLE', 'SNAPSHOT']
         end

lib/active_record/connection_adapters/sqlserver/schema_statements.rb

@@ -156,6 +156,7 @@ def views
           tables('VIEW')
         end
 
+
         protected
 
         # === SQLServer Specific ======================================== #
@@ -421,21 +422,6 @@ def update_sql?(sql)
           !(sql =~ /^\s*(UPDATE|EXEC sp_executesql N'UPDATE)/i).nil?
         end
 
-        def with_identity_insert_enabled(table_name)
-          table_name = quote_table_name(table_name_or_views_table_name(table_name))
-          set_identity_insert(table_name, true)
-          yield
-        ensure
-          set_identity_insert(table_name, false)
-        end
-
-        def set_identity_insert(table_name, enable = true)
-          sql = "SET IDENTITY_INSERT #{table_name} #{enable ? 'ON' : 'OFF'}"
-          do_execute sql, 'SCHEMA'
-        rescue Exception
-          raise ActiveRecordError, "IDENTITY_INSERT could not be turned #{enable ? 'ON' : 'OFF'} for table #{table_name}"
-        end
-
         def identity_column(table_name)
           schema_cache.columns(table_name).find(&:is_identity?)
         end

test/cases/adapter_test_sqlserver.rb

@@ -446,14 +446,10 @@ class AdapterTestSQLServer < ActiveRecord::TestCase
 
     # Doing identity inserts
 
-    let(:view_insert_sql) { "INSERT INTO [sst_customers_view] ([id],[name],[balance]) VALUES (420,'Microsoft',0)" }
-
-    it 'respond true/tablename to #query_requires_identity_insert?' do
-      assert_equal '[sst_customers_view]', connection.send(:query_requires_identity_insert?, view_insert_sql)
-    end
-
     it 'be able to do an identity insert' do
-      assert_nothing_raised { connection.execute( view_insert_sql) }
+      customer = SSTestCustomersView.new
+      customer.id = 420
+      customer.save!
       assert SSTestCustomersView.find(420)
     end
 

test/cases/coerced_tests.rb

@@ -70,6 +70,14 @@ def test_not_eq_with_array_parameter_coerced
 require 'models/company'
 class InheritanceTest < ActiveRecord::TestCase
 
+  coerce_tests! :test_a_bad_type_column
+  def test_a_bad_type_column_coerced
+    Company.connection.with_identity_insert_enabled('companies') do
+      Company.connection.insert "INSERT INTO companies (id, #{QUOTED_TYPE}, name) VALUES(100, 'bad_class!', 'Not happening')"
+    end
+    assert_raise(ActiveRecord::SubclassNotFound) { Company.find(100) }
+  end
+
   coerce_tests! :test_eager_load_belongs_to_primary_key_quoting
   def test_eager_load_belongs_to_primary_key_quoting_coerced
     con = Account.connection