示例#1
0
文件: datum.go 项目: yangxuanjia/tidb
func (d *Datum) convertToMysqlSet(target *FieldType) (Datum, error) {
	var (
		ret Datum
		s   mysql.Set
		err error
	)
	switch d.k {
	case KindString, KindBytes:
		s, err = mysql.ParseSetName(target.Elems, d.GetString())
	default:
		var uintDatum Datum
		uintDatum, err = d.convertToUint(target)
		if err != nil {
			return ret, errors.Trace(err)
		}
		s, err = mysql.ParseSetValue(target.Elems, uintDatum.GetUint64())
	}

	if err != nil {
		return invalidConv(d, target.Tp)
	}
	ret.SetValue(s)
	return ret, nil
}
示例#2
0
// Convert converts the val with type tp.
func Convert(val interface{}, target *FieldType) (v interface{}, err error) {
	tp := target.Tp
	if val == nil {
		return nil, nil
	}
	vdi, ok := val.(*DataItem)
	if ok {
		return Convert(vdi.Data, target)
	}
	switch tp { // TODO: implement mysql types convert when "CAST() AS" syntax are supported.
	case mysql.TypeFloat:
		x, err := ToFloat64(val)
		if err != nil {
			return invConv(val, tp)
		}
		// For float and following double type, we will only truncate it for float(M, D) format.
		// If no D is set, we will handle it like origin float whether M is set or not.
		if target.Flen != UnspecifiedLength && target.Decimal != UnspecifiedLength {
			x, err = TruncateFloat(x, target.Flen, target.Decimal)
			if err != nil {
				return nil, errors.Trace(err)
			}
		}
		return float32(x), nil
	case mysql.TypeDouble:
		x, err := ToFloat64(val)
		if err != nil {
			return invConv(val, tp)
		}
		if target.Flen != UnspecifiedLength && target.Decimal != UnspecifiedLength {
			x, err = TruncateFloat(x, target.Flen, target.Decimal)
			if err != nil {
				return nil, errors.Trace(err)
			}
		}
		return float64(x), nil
	case mysql.TypeBlob, mysql.TypeTinyBlob, mysql.TypeMediumBlob, mysql.TypeLongBlob,
		mysql.TypeString, mysql.TypeVarchar, mysql.TypeVarString:
		x, err := ToString(val)
		if err != nil {
			return invConv(val, tp)
		}
		// TODO: consider target.Charset/Collate
		x = truncateStr(x, target.Flen)
		if target.Charset == charset.CharsetBin {
			return []byte(x), nil
		}
		return x, nil
	case mysql.TypeDuration:
		fsp := mysql.DefaultFsp
		if target.Decimal != UnspecifiedLength {
			fsp = target.Decimal
		}
		switch x := val.(type) {
		case mysql.Duration:
			return x.RoundFrac(fsp)
		case mysql.Time:
			t, err := x.ConvertToDuration()
			if err != nil {
				return nil, errors.Trace(err)
			}

			return t.RoundFrac(fsp)
		case string:
			return mysql.ParseDuration(x, fsp)
		default:
			return invConv(val, tp)
		}
	case mysql.TypeTimestamp, mysql.TypeDatetime, mysql.TypeDate:
		fsp := mysql.DefaultFsp
		if target.Decimal != UnspecifiedLength {
			fsp = target.Decimal
		}
		switch x := val.(type) {
		case mysql.Time:
			t, err := x.Convert(tp)
			if err != nil {
				return nil, errors.Trace(err)
			}
			return t.RoundFrac(fsp)
		case mysql.Duration:
			t, err := x.ConvertToTime(tp)
			if err != nil {
				return nil, errors.Trace(err)
			}
			return t.RoundFrac(fsp)
		case string:
			return mysql.ParseTime(x, tp, fsp)
		case int64:
			return mysql.ParseTimeFromNum(x, tp, fsp)
		default:
			return invConv(val, tp)
		}
	case mysql.TypeTiny, mysql.TypeShort, mysql.TypeInt24, mysql.TypeLong, mysql.TypeLonglong:
		unsigned := mysql.HasUnsignedFlag(target.Flag)
		if unsigned {
			return convertToUint(val, target)
		}
		return convertToInt(val, target)
	case mysql.TypeBit:
		x, err := convertToUint(val, target)
		if err != nil {
			return x, errors.Trace(err)
		}

		// check bit boundary, if bit has n width, the boundary is
		// in [0, (1 << n) - 1]
		width := target.Flen
		if width == 0 || width == mysql.UnspecifiedBitWidth {
			width = mysql.MinBitWidth
		}

		maxValue := uint64(1)<<uint64(width) - 1

		if x > maxValue {
			return maxValue, overflow(val, tp)
		}
		return mysql.Bit{Value: x, Width: width}, nil
	case mysql.TypeDecimal, mysql.TypeNewDecimal:
		x, err := ToDecimal(val)
		if err != nil {
			return invConv(val, tp)
		}
		if target.Decimal != UnspecifiedLength {
			x = x.Round(int32(target.Decimal))
		}
		// TODO: check Flen
		return x, nil
	case mysql.TypeYear:
		var (
			intVal int64
			err    error
		)
		switch x := val.(type) {
		case string:
			intVal, err = StrToInt(x)
		case mysql.Time:
			return int64(x.Year()), nil
		case mysql.Duration:
			return int64(time.Now().Year()), nil
		default:
			intVal, err = ToInt64(x)
		}
		if err != nil {
			return invConv(val, tp)
		}
		y, err := mysql.AdjustYear(int(intVal))
		if err != nil {
			return invConv(val, tp)
		}
		return int64(y), nil
	case mysql.TypeEnum:
		var (
			e   mysql.Enum
			err error
		)
		switch x := val.(type) {
		case string:
			e, err = mysql.ParseEnumName(target.Elems, x)
		case []byte:
			e, err = mysql.ParseEnumName(target.Elems, string(x))
		default:
			var number uint64
			number, err = ToUint64(x)
			if err != nil {
				return nil, errors.Trace(err)
			}
			e, err = mysql.ParseEnumValue(target.Elems, number)
		}

		if err != nil {
			return invConv(val, tp)
		}
		return e, nil
	case mysql.TypeSet:
		var (
			s   mysql.Set
			err error
		)
		switch x := val.(type) {
		case string:
			s, err = mysql.ParseSetName(target.Elems, x)
		case []byte:
			s, err = mysql.ParseSetName(target.Elems, string(x))
		default:
			var number uint64
			number, err = ToUint64(x)
			if err != nil {
				return nil, errors.Trace(err)
			}
			s, err = mysql.ParseSetValue(target.Elems, number)
		}

		if err != nil {
			return invConv(val, tp)
		}
		return s, nil
	case mysql.TypeNull:
		return nil, nil
	default:
		panic("should never happen")
	}
}