diff --git a/association_test.go b/association_test.go
index c2f55d0e..8ba198e5 100644
--- a/association_test.go
+++ b/association_test.go
@@ -600,7 +600,9 @@ func TestRelated(t *testing.T) {
 		Company:         Company{Name: "company1"},
 	}
 
-	DB.Save(&user)
+	if err := DB.Save(&user).Error; err != nil {
+		t.Errorf("No error should happen when saving user")
+	}
 
 	if user.CreditCard.ID == 0 {
 		t.Errorf("After user save, credit card should have id")
diff --git a/field.go b/field.go
index 79e2c0ec..2ed4e732 100644
--- a/field.go
+++ b/field.go
@@ -13,7 +13,7 @@ type Field struct {
 	Field   reflect.Value
 }
 
-func (field *Field) Set(value interface{}) error {
+func (field *Field) Set(value interface{}) (err error) {
 	if !field.Field.IsValid() {
 		return errors.New("field value not valid")
 	}
@@ -27,15 +27,25 @@ func (field *Field) Set(value interface{}) error {
 		reflectValue = reflect.ValueOf(value)
 	}
 
+	fieldValue := field.Field
 	if reflectValue.IsValid() {
-		if reflectValue.Type().ConvertibleTo(field.Field.Type()) {
-			field.Field.Set(reflectValue.Convert(field.Field.Type()))
-		} else if scanner, ok := field.Field.Addr().Interface().(sql.Scanner); ok {
-			if err := scanner.Scan(reflectValue.Interface()); err != nil {
-				return err
-			}
+		if reflectValue.Type().ConvertibleTo(fieldValue.Type()) {
+			fieldValue.Set(reflectValue.Convert(fieldValue.Type()))
 		} else {
-			return fmt.Errorf("could not convert argument of field %s from %s to %s", field.Name, reflectValue.Type(), field.Field.Type())
+			if fieldValue.Kind() == reflect.Ptr {
+				if fieldValue.IsNil() {
+					fieldValue.Set(reflect.New(field.Struct.Type.Elem()))
+				}
+				fieldValue = fieldValue.Elem()
+			}
+
+			if reflectValue.Type().ConvertibleTo(fieldValue.Type()) {
+				fieldValue.Set(reflectValue.Convert(fieldValue.Type()))
+			} else if scanner, ok := fieldValue.Addr().Interface().(sql.Scanner); ok {
+				err = scanner.Scan(reflectValue.Interface())
+			} else {
+				err = fmt.Errorf("could not convert argument of field %s from %s to %s", field.Name, reflectValue.Type(), fieldValue.Type())
+			}
 		}
 	} else {
 		field.Field.Set(reflect.Zero(field.Field.Type()))
diff --git a/preload.go b/preload.go
index 20c9aacf..692280ef 100644
--- a/preload.go
+++ b/preload.go
@@ -7,7 +7,6 @@ import (
 	"strings"
 )
 
-// Preload preload relations callback
 func Preload(scope *Scope) {
 	if scope.Search.preload == nil || scope.HasError() {
 		return
diff --git a/query_test.go b/query_test.go
index 71ced650..a7d5bc0e 100644
--- a/query_test.go
+++ b/query_test.go
@@ -207,10 +207,12 @@ func TestSearchWithStruct(t *testing.T) {
 }
 
 func TestSearchWithMap(t *testing.T) {
+	companyID := 1
 	user1 := User{Name: "MapSearchUser1", Age: 1, Birthday: now.MustParse("2000-1-1")}
 	user2 := User{Name: "MapSearchUser2", Age: 10, Birthday: now.MustParse("2010-1-1")}
 	user3 := User{Name: "MapSearchUser3", Age: 20, Birthday: now.MustParse("2020-1-1")}
-	DB.Save(&user1).Save(&user2).Save(&user3)
+	user4 := User{Name: "MapSearchUser4", Age: 30, Birthday: now.MustParse("2020-1-1"), CompanyID: &companyID}
+	DB.Save(&user1).Save(&user2).Save(&user3).Save(&user4)
 
 	var user User
 	DB.First(&user, map[string]interface{}{"name": user1.Name})
@@ -234,6 +236,21 @@ func TestSearchWithMap(t *testing.T) {
 	if len(users) != 1 {
 		t.Errorf("Search all records with inline map")
 	}
+
+	DB.Find(&users, map[string]interface{}{"name": user4.Name, "company_id": nil})
+	if len(users) != 0 {
+		t.Errorf("Search all records with inline map containing null value finding 0 records")
+	}
+
+	DB.Find(&users, map[string]interface{}{"name": user1.Name, "company_id": nil})
+	if len(users) != 1 {
+		t.Errorf("Search all records with inline map containing null value finding 1 record")
+	}
+
+	DB.Find(&users, map[string]interface{}{"name": user4.Name, "company_id": companyID})
+	if len(users) != 1 {
+		t.Errorf("Search all records with inline multiple value map")
+	}
 }
 
 func TestSearchWithEmptyChain(t *testing.T) {
@@ -377,10 +394,14 @@ func TestNot(t *testing.T) {
 	DB.Create(getPreparedUser("user1", "not"))
 	DB.Create(getPreparedUser("user2", "not"))
 	DB.Create(getPreparedUser("user3", "not"))
-	DB.Create(getPreparedUser("user4", "not"))
+
+	user4 := getPreparedUser("user4", "not")
+	user4.Company = Company{}
+	DB.Create(user4)
+
 	DB := DB.Where("role = ?", "not")
 
-	var users1, users2, users3, users4, users5, users6, users7, users8 []User
+	var users1, users2, users3, users4, users5, users6, users7, users8, users9 []User
 	if DB.Find(&users1).RowsAffected != 4 {
 		t.Errorf("should find 4 not users")
 	}
@@ -423,15 +444,20 @@ func TestNot(t *testing.T) {
 		t.Errorf("Should find all users's name not equal 3")
 	}
 
-	DB.Not("name", []string{"user3"}).Find(&users7)
-	if len(users1)-len(users7) != int(name3Count) {
+	DB.Not(map[string]interface{}{"name": "user3", "company_id": nil}).Find(&users7)
+	if len(users1)-len(users7) != 2 { // not user3 or user4
+		t.Errorf("Should find all user's name not equal to 3 who do not have company id")
+	}
+
+	DB.Not("name", []string{"user3"}).Find(&users8)
+	if len(users1)-len(users8) != int(name3Count) {
 		t.Errorf("Should find all users's name not equal 3")
 	}
 
 	var name2Count int64
 	DB.Table("users").Where("name = ?", "user2").Count(&name2Count)
-	DB.Not("name", []string{"user3", "user2"}).Find(&users8)
-	if len(users1)-len(users8) != (int(name3Count) + int(name2Count)) {
+	DB.Not("name", []string{"user3", "user2"}).Find(&users9)
+	if len(users1)-len(users9) != (int(name3Count) + int(name2Count)) {
 		t.Errorf("Should find all users's name not equal 3")
 	}
 }
diff --git a/scope_private.go b/scope_private.go
index a9288bb2..9d0283d7 100644
--- a/scope_private.go
+++ b/scope_private.go
@@ -32,7 +32,11 @@ func (scope *Scope) buildWhereCondition(clause map[string]interface{}) (str stri
 	case map[string]interface{}:
 		var sqls []string
 		for key, value := range value {
-			sqls = append(sqls, fmt.Sprintf("(%v = %v)", scope.Quote(key), scope.AddToVars(value)))
+			if value != nil {
+				sqls = append(sqls, fmt.Sprintf("(%v = %v)", scope.Quote(key), scope.AddToVars(value)))
+			} else {
+				sqls = append(sqls, fmt.Sprintf("(%v IS NULL)", scope.Quote(key)))
+			}
 		}
 		return strings.Join(sqls, " AND ")
 	case interface{}:
@@ -98,7 +102,11 @@ func (scope *Scope) buildNotCondition(clause map[string]interface{}) (str string
 	case map[string]interface{}:
 		var sqls []string
 		for key, value := range value {
-			sqls = append(sqls, fmt.Sprintf("(%v <> %v)", scope.Quote(key), scope.AddToVars(value)))
+			if value != nil {
+				sqls = append(sqls, fmt.Sprintf("(%v <> %v)", scope.Quote(key), scope.AddToVars(value)))
+			} else {
+				sqls = append(sqls, fmt.Sprintf("(%v IS NOT NULL)", scope.Quote(key)))
+			}
 		}
 		return strings.Join(sqls, " AND ")
 	case interface{}:
diff --git a/structs_test.go b/structs_test.go
index e595df58..42eb6bc3 100644
--- a/structs_test.go
+++ b/structs_test.go
@@ -28,7 +28,7 @@ type User struct {
 	CreditCard        CreditCard
 	Latitude          float64
 	Languages         []Language `gorm:"many2many:user_languages;"`
-	CompanyID         int64
+	CompanyID         *int
 	Company           Company
 	Role
 	PasswordHash      []byte
diff --git a/utils_private.go b/utils_private.go
index f8f918fb..c4f0e963 100644
--- a/utils_private.go
+++ b/utils_private.go
@@ -87,9 +87,10 @@ func toString(str interface{}) string {
 		return strings.Join(results, "_")
 	} else if bytes, ok := str.([]byte); ok {
 		return string(bytes)
-	} else {
-		return fmt.Sprintf("%v", str)
+	} else if reflectValue := reflect.Indirect(reflect.ValueOf(str)); reflectValue.IsValid() {
+		return fmt.Sprintf("%v", reflectValue.Interface())
 	}
+	return ""
 }
 
 func makeSlice(elemType reflect.Type) interface{} {