}
		sort.Strings(keys)

		for _, k := range keys {
			kv := value[k]
			if _, ok := kv.(*gorm.DB); ok {
				kv = []interface{}{kv}
			}

			if stmt.Schema != nil {
				if field := stmt.Schema.LookUpField(k); field != nil {
					if field.DBName != "" {
						if v, ok := selectColumns[field.DBName]; (ok && v) || (!ok && !restricted) {
							set = append(set, clause.Assignment{Column: clause.Column{Name: field.DBName}, Value: kv})

func prepareValues(values []interface{}, db *DB, columnTypes []*sql.ColumnType, columns []string) {
	if db.Statement.Schema != nil {
		for idx, name := range columns {
			if field := db.Statement.Schema.LookUpField(name); field != nil {
				values[idx] = reflect.New(reflect.PointerTo(field.FieldType)).Interface()
				continue
			}
			values[idx] = new(interface{})
		}
	} else if len(columnTypes) > 0 {

			ForeignKey:   relation.Polymorphic.PolymorphicType,
		})

		primaryKeyField := schema.PrioritizedPrimaryField
		if len(relation.foreignKeys) > 0 {
			if primaryKeyField = schema.LookUpField(relation.foreignKeys[0]); primaryKeyField == nil || len(relation.foreignKeys) > 1 {
				schema.err = fmt.Errorf("invalid polymorphic foreign keys %+v for %v on field %s", relation.foreignKeys,
					schema, field.Name)
			}

	return m.RunWithValue(value, func(stmt *gorm.Statement) error {
		if stmt.Schema != nil {
			if field := stmt.Schema.LookUpField(oldName); field != nil {
				oldName = field.DBName
			}

			if field := stmt.Schema.LookUpField(newName); field != nil {
				newName = field.DBName
			}
		}

		return m.DB.Exec(
			"ALTER TABLE ? RENAME COLUMN ? TO ?",

					switch column := eq.Column.(type) {
					case string:
						if field := db.Statement.Schema.LookUpField(column); field != nil {
							db.AddError(field.Set(db.Statement.Context, db.Statement.ReflectValue, eq.Value))
						}
					case clause.Column:
						if field := db.Statement.Schema.LookUpField(column.Name); field != nil {
							db.AddError(field.Set(db.Statement.Context, db.Statement.ReflectValue, eq.Value))
						}

	}

	if name := DB.Dialector.Name(); name == "postgres" || name == "mysql" || name == "gaussdb" {
		stmt := gorm.Statement{DB: DB}
		stmt.Parse(&Blog{})
		stmt.Schema.LookUpField("ID").Unique = true
		stmt.Parse(&Tag{})
		stmt.Schema.LookUpField("ID").Unique = true
		// postgers only allow unique constraint matching given keys
	}

	DB.Migrator().DropTable(&Blog{}, &Tag{}, "blog_tags", "locale_blog_tags", "shared_blog_tags")

			for idx, name := range db.Statement.Selects {
				if db.Statement.Schema == nil {
					clauseSelect.Columns[idx] = clause.Column{Name: name, Raw: true}
				} else if f := db.Statement.Schema.LookUpField(name); f != nil {
					clauseSelect.Columns[idx] = clause.Column{Name: f.DBName}
				} else {
					clauseSelect.Columns[idx] = clause.Column{Name: name, Raw: true}
				}
			}

				selectColumns, restricted := stmt.SelectAndOmitColumns(true, true)

				columns := make([]string, 0, len(values.Columns)-1)
				for _, column := range values.Columns {
					if field := stmt.Schema.LookUpField(column.Name); field != nil {
						if v, ok := selectColumns[field.DBName]; (ok && v) || (!ok && !restricted) {
							if !field.PrimaryKey && (!field.HasDefaultValue || field.DefaultValueInterface != nil ||

	isRelation := ok && relation.JoinTable != nil
	if !isRelation {
		return fmt.Errorf("failed to find relation: %s", field)
	}

	for _, ref := range relation.References {
		f := joinSchema.LookUpField(ref.ForeignKey.DBName)
		if f == nil {
			return fmt.Errorf("missing field %s for join table", ref.ForeignKey.DBName)
		}

		f.DataType = ref.ForeignKey.DataType
		f.GORMDataType = ref.ForeignKey.GORMDataType