Golang Datum.ResolvedType方法代碼示例

// DatumToEncDatumWithInferredType initializes an EncDatum with the given
// Datum, setting its Type automatically. This does not work if the base
// Datum's type is DNull, in which case an error is returned.
func DatumToEncDatumWithInferredType(datum parser.Datum) (EncDatum, error) {
	dType, ok := ColumnType_Kind_value[strings.ToUpper(datum.ResolvedType().String())]
	if !ok {
		return EncDatum{}, errors.Errorf(
			"Unknown type %s, could not convert to EncDatum", datum.ResolvedType())
	}
	return DatumToEncDatum(ColumnType_Kind(dType), datum), nil
}

// SetDatum initializes the EncDatum with the given Datum.
func (ed *EncDatum) SetDatum(typ ColumnType_Kind, d parser.Datum) {
	if d == nil {
		panic("nil datum given")
	}
	if d != parser.DNull && !typ.ToDatumType().Equal(d.ResolvedType()) {
		panic(fmt.Sprintf("invalid datum type given: %s, expected %s",
			d.ResolvedType(), typ.ToDatumType()))
	}
	ed.Type = typ
	ed.encoded = nil
	ed.Datum = d
}

// DatumToEncDatum initializes an EncDatum with the given Datum.
func DatumToEncDatum(ctyp ColumnType, d parser.Datum) EncDatum {
	if d == nil {
		panic("Cannot convert nil datum to EncDatum")
	}
	if ptyp := ctyp.ToDatumType(); d != parser.DNull && !ptyp.Equal(d.ResolvedType()) {
		panic(fmt.Sprintf("invalid datum type given: %s, expected %s",
			d.ResolvedType(), ptyp))
	}
	return EncDatum{
		Type:  ctyp,
		Datum: d,
	}
}

// MarshalColumnValue returns a Go primitive value equivalent of val, of the
// type expected by col. If val's type is incompatible with col, or if
// col's type is not yet implemented, an error is returned.
func MarshalColumnValue(col ColumnDescriptor, val parser.Datum) (roachpb.Value, error) {
	var r roachpb.Value

	if val == parser.DNull {
		return r, nil
	}

	switch col.Type.Kind {
	case ColumnType_BOOL:
		if v, ok := val.(*parser.DBool); ok {
			r.SetBool(bool(*v))
			return r, nil
		}
	case ColumnType_INT:
		if v, ok := val.(*parser.DInt); ok {
			r.SetInt(int64(*v))
			return r, nil
		}
	case ColumnType_FLOAT:
		if v, ok := val.(*parser.DFloat); ok {
			r.SetFloat(float64(*v))
			return r, nil
		}
	case ColumnType_DECIMAL:
		if v, ok := val.(*parser.DDecimal); ok {
			err := r.SetDecimal(&v.Dec)
			return r, err
		}
	case ColumnType_STRING:
		if v, ok := val.(*parser.DString); ok {
			r.SetString(string(*v))
			return r, nil
		}
	case ColumnType_BYTES:
		if v, ok := val.(*parser.DBytes); ok {
			r.SetString(string(*v))
			return r, nil
		}
		if v, ok := val.(*parser.DString); ok {
			r.SetString(string(*v))
			return r, nil
		}
	case ColumnType_DATE:
		if v, ok := val.(*parser.DDate); ok {
			r.SetInt(int64(*v))
			return r, nil
		}
	case ColumnType_TIMESTAMP:
		if v, ok := val.(*parser.DTimestamp); ok {
			r.SetTime(v.Time)
			return r, nil
		}
	case ColumnType_TIMESTAMPTZ:
		if v, ok := val.(*parser.DTimestampTZ); ok {
			r.SetTime(v.Time)
			return r, nil
		}
	case ColumnType_INTERVAL:
		if v, ok := val.(*parser.DInterval); ok {
			err := r.SetDuration(v.Duration)
			return r, err
		}
	default:
		return r, errors.Errorf("unsupported column type: %s", col.Type.Kind)
	}
	return r, fmt.Errorf("value type %s doesn't match type %s of column %q",
		val.ResolvedType(), col.Type.Kind, col.Name)
}