Create and drop view

migrator.go

@@ -30,8 +30,8 @@ func (db *DB) AutoMigrate(dst ...interface{}) error {
 
 // ViewOption view option
 type ViewOption struct {
-	Replace     bool
-	CheckOption string
+	Replace     bool   // CREATE [ OR REPLACE ]
+	CheckOption string // WITH [ CASCADED | LOCAL ] CHECK OPTION
 	Query       *DB
 }
 

migrator/migrator.go

@@ -559,12 +559,27 @@ func (m Migrator) ColumnTypes(value interface{}) ([]gorm.ColumnType, error) {
 
 // CreateView create view
 func (m Migrator) CreateView(name string, option gorm.ViewOption) error {
-	return gorm.ErrNotImplemented
+	sql := new(strings.Builder)
+	sql.WriteString("CREATE ")
+	if option.Replace {
+		sql.WriteString("OR REPLACE ")
+	}
+	sql.WriteString("VIEW ")
+	m.QuoteTo(sql, name)
+	sql.WriteString(" AS ")
+
+	m.DB.Statement.AddVar(sql, option.Query)
+
+	if option.CheckOption != "" {
+		sql.WriteString(" ")
+		sql.WriteString(option.CheckOption)
+	}
+	return m.DB.Exec(sql.String()).Error
 }
 
 // DropView drop view
 func (m Migrator) DropView(name string) error {
-	return gorm.ErrNotImplemented
+	return m.DB.Exec("DROP VIEW IF EXISTS ?", clause.Table{Name: name}).Error
 }
 
 func buildConstraint(constraint *schema.Constraint) (sql string, results []interface{}) {

tests/migrate_test.go

@@ -1509,3 +1509,24 @@ func TestMigrateIgnoreRelations(t *testing.T) {
 		t.Errorf("RelationModel2 should not be migrated")
 	}
 }
+
+func TestMigrateView(t *testing.T) {
+	DB.Save(GetUser("joins-args-db", Config{Pets: 2}))
+
+	query := DB.Model(&User{}).
+		Select("users.id as users_id, users.name as users_name, pets.id as pets_id, pets.name as pets_name").
+		Joins("inner join pets on pets.user_id = users.id")
+
+	if err := DB.Migrator().CreateView("users_pets", gorm.ViewOption{Query: query}); err != nil {
+		t.Fatalf("Failed to crate view, got %v", err)
+	}
+
+	var count int64
+	if err := DB.Table("users_pets").Count(&count).Error; err != nil {
+		t.Fatalf("should found created view")
+	}
+
+	if err := DB.Migrator().DropView("users_pets"); err != nil {
+		t.Fatalf("Failed to drop view, got %v", err)
+	}
+}