MySQL 的位类型映射到哪个 Go 类型?
我之前用过Java，所以数据库表中有些列的类型是bit(1).但是现在我想用 beego 来重建我的项目，我不想改变我的数据库表(需要做很多).我在我的项目中使用 beego 的 orm.那么我应该使用哪种 Go 类型?
I used Java before, so some columns' type in database table is bit(1). But now I want to use beego to rebuild my project and I don't want to alter my database table (need do much). I use beego's orm in my project. So which Go type should I use?
这样的表和删除的列有问题:
Table like this and the deleted column has the question:
+--------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------+--------------+------+-----+---------+-------+
| id | varchar(255) | NO | PRI | NULL | |
| created_time | datetime | YES | | NULL | |
| deleted | bit(1) | NO | | NULL | |
| updated_time | datetime | YES | | NULL | |
| icon_class | varchar(255) | YES | | NULL | |
| mark | varchar(255) | YES | | NULL | |
| name | varchar(255) | YES | | NULL | |
| parent | varchar(255) | YES | | NULL | |
+--------------+--------------+------+-----+---------+-------+
像这样去结构:
type BaseModel struct {
Id string `orm:"pk";form:"id"`
CreatedTime time.Time `orm:"auto_now_add;type(datetime)";form:"-"`
UpdatedTime time.Time `orm:"auto_now;type(datetime)";form:"-"`
Deleted bool `form:"-"`
}
当我在我的代码中使用 bool 时，错误如下:
When I use bool in my code, the error like this:
`[0]` convert to `*orm.BooleanField` failed, field: shareall-go/models.Category.BaseModel.Deleted err: strconv.ParseBool: parsing "x00": invalid syntax
推荐答案
Sqlx 还为这种情况创建了一个自定义的 bool 数据类型并且它工作正常.相关代码链接
Sqlx has created also a custom bool datatype for such situations and it works fine. Link to related code
// BitBool is an implementation of a bool for the MySQL type BIT(1).
// This type allows you to avoid wasting an entire byte for MySQL's boolean type TINYINT.
type BitBool bool
// Value implements the driver.Valuer interface,
// and turns the BitBool into a bitfield (BIT(1)) for MySQL storage.
func (b BitBool) Value() (driver.Value, error) {
if b {
return []byte{1}, nil
} else {
return []byte{0}, nil
}
}
// Scan implements the sql.Scanner interface,
// and turns the bitfield incoming from MySQL into a BitBool
func (b *BitBool) Scan(src interface{}) error {
v, ok := src.([]byte)
if !ok {
return errors.New("bad []byte type assertion")
}
*b = v[0] == 1
return nil
}