code: func (d *Datum) GetValue() interface{} {
  	switch d.k {
  	case KindInt64:
  		return d.GetInt64()
  	case KindUint64:
  		return d.GetUint64()
  	case KindFloat32:
  		return d.GetFloat32()
  	case KindFloat64:
  		return d.GetFloat64()
  	case KindString:
  		return d.GetString()
  	case KindBytes:
  		return d.GetBytes()
  	case KindMysqlDecimal:
  		return d.GetMysqlDecimal()
  	case KindMysqlDuration:
  		return d.GetMysqlDuration()
  	case KindMysqlEnum:
  		return d.GetMysqlEnum()
  	case KindBinaryLiteral, KindMysqlBit:
  		return d.GetBinaryLiteral()
  	case KindMysqlSet:
  		return d.GetMysqlSet()
  	case KindMysqlJSON:
  		return d.GetMysqlJSON()
  	case KindMysqlTime:
  		return d.GetMysqlTime()
  	default:
  		return d.GetInterface()
  	}
  }
docs: // GetValue gets the value of the datum of any kind.