code: func (c *Column) GetTypeDesc() string {
  	desc := c.FieldType.CompactStr()
  	if mysql.HasUnsignedFlag(c.Flag) && c.Tp != mysql.TypeBit && c.Tp != mysql.TypeYear {
  		desc += " unsigned"
  	}
  	if mysql.HasZerofillFlag(c.Flag) && c.Tp != mysql.TypeYear {
  		desc += " zerofill"
  	}
  	return desc
  }
docs: // GetTypeDesc gets the description for column type.