Golang Time.RoundFrac方法代碼示例

func builtinNow(args []interface{}, ctx map[interface{}]interface{}) (interface{}, error) {
	// TODO: if NOW is used in stored function or trigger, NOW will return the beginning time
	// of the execution.
	fsp := 0
	if len(args) == 1 {
		var err error
		if fsp, err = checkFsp(args[0]); err != nil {
			return nil, errors.Trace(err)
		}
	}

	t := mysql.Time{
		Time: time.Now(),
		Type: mysql.TypeDatetime,
		// set unspecified for later round
		Fsp: mysql.UnspecifiedFsp,
	}

	return t.RoundFrac(int(fsp))
}

func builtinNow(args []interface{}, ctx map[interface{}]interface{}) (interface{}, error) {
	fsp := int64(0)
	if len(args) == 1 {
		var err error
		fsp, err = types.ToInt64(args[0])
		if err != nil {
			return nil, errors.Trace(err)
		}
		if int(fsp) > mysql.MaxFsp {
			return nil, errors.Errorf("Too big precision %d specified. Maximum is 6.", fsp)
		} else if fsp < 0 {
			return nil, errors.Errorf("Invalid negative %d specified, must in [0, 6].", fsp)
		}
	}

	t := mysql.Time{
		Time: time.Now(),
		Type: mysql.TypeDatetime,
		// set unspecified for later round
		Fsp: mysql.UnspecifiedFsp,
	}

	return t.RoundFrac(int(fsp))
}

// Cast casts val to certain types and does not return error.
func Cast(val interface{}, target *FieldType) (v interface{}) { //NTYPE
	tp := target.Tp
	switch tp {
	case mysql.TypeString:
		x, _ := ToString(val)
		// TODO: consider target.Charset/Collate
		x = truncateStr(x, target.Flen)
		if target.Charset == charset.CharsetBin {
			return []byte(x)
		}
		return x
	case mysql.TypeDuration:
		var dur mysql.Duration
		fsp := mysql.DefaultFsp
		if target.Decimal != UnspecifiedLength {
			fsp = target.Decimal
		}
		switch x := val.(type) {
		case mysql.Duration:
			dur, _ = x.RoundFrac(fsp)
		case mysql.Time:
			dur, _ = x.ConvertToDuration()
			dur, _ = dur.RoundFrac(fsp)
		case string:
			dur, _ = mysql.ParseDuration(x, fsp)
		}
		return dur
	case mysql.TypeDatetime, mysql.TypeDate:
		fsp := mysql.DefaultFsp
		if target.Decimal != UnspecifiedLength {
			fsp = target.Decimal
		}
		var t mysql.Time
		t.Type = tp
		switch x := val.(type) {
		case mysql.Time:
			t, _ = x.Convert(tp)
			t, _ = t.RoundFrac(fsp)
		case mysql.Duration:
			t, _ = x.ConvertToTime(tp)
			t, _ = t.RoundFrac(fsp)
		case string:
			t, _ = mysql.ParseTime(x, tp, fsp)
		case int64:
			t, _ = mysql.ParseTimeFromNum(x, tp, fsp)
		}
		return t
	case mysql.TypeLonglong:
		if mysql.HasUnsignedFlag(target.Flag) {
			v, _ = ToUint64(val)
		} else {
			v, _ = ToInt64(val)
		}
		return
	case mysql.TypeNewDecimal:
		x, _ := ToDecimal(val)
		if target.Decimal != UnspecifiedLength {
			x = x.Round(int32(target.Decimal))
		}
		// TODO: check Flen
		return x
	default:
		panic("should never happen")
	}
}

// CastValue casts a value based on column's type.
func (c *Col) CastValue(ctx context.Context, val interface{}) (casted interface{}, err error) {
	if val == nil {
		return
	}
	switch c.Tp {
	case mysql.TypeTiny, mysql.TypeShort, mysql.TypeInt24, mysql.TypeLong, mysql.TypeLonglong, mysql.TypeYear, mysql.TypeBit:
		intVal, errCode := c.normalizeIntegerValue(val)
		if errCode == errCodeType {
			casted = intVal
			err = c.TypeError(val)
			return
		}
		return c.castIntegerValue(intVal, errCode)
	case mysql.TypeFloat, mysql.TypeDouble:
		return c.castFloatValue(val)
	case mysql.TypeDate, mysql.TypeDatetime, mysql.TypeTimestamp:
		switch v := val.(type) {
		case int64:
			casted, err = mysql.ParseTimeFromNum(v, c.Tp, c.Decimal)
			if err != nil {
				err = newParseColError(err, c)
			}
		case string:
			casted, err = mysql.ParseTime(v, c.Tp, c.Decimal)
			if err != nil {
				err = newParseColError(err, c)
			}
		case mysql.Time:
			var t mysql.Time
			t, err = v.Convert(c.Tp)
			if err != nil {
				err = newParseColError(err, c)
				return
			}
			casted, err = t.RoundFrac(c.Decimal)
			if err != nil {
				err = newParseColError(err, c)
			}
		default:
			err = c.TypeError(val)
		}
	case mysql.TypeDuration:
		switch v := val.(type) {
		case string:
			casted, err = mysql.ParseDuration(v, c.Decimal)
			if err != nil {
				err = newParseColError(err, c)
			}
		case mysql.Time:
			var t mysql.Duration
			t, err = v.ConvertToDuration()
			if err != nil {
				err = newParseColError(err, c)
				return
			}
			casted, err = t.RoundFrac(c.Decimal)
			if err != nil {
				err = newParseColError(err, c)
			}
		case mysql.Duration:
			casted, err = v.RoundFrac(c.Decimal)
		default:
			err = c.TypeError(val)
		}
	case mysql.TypeBlob, mysql.TypeTinyBlob, mysql.TypeMediumBlob, mysql.TypeLongBlob, mysql.TypeString, mysql.TypeVarchar, mysql.TypeVarString:
		strV := ""
		switch v := val.(type) {
		case mysql.Time:
			strV = v.String()
		case mysql.Duration:
			strV = v.String()
		case []byte:
			if c.Charset == charset.CharsetBin {
				casted = v
				return
			}
			strV = string(v)
		default:
			strV = fmt.Sprintf("%v", val)
		}
		if (c.Flen != types.UnspecifiedLength) && (len(strV) > c.Flen) {
			strV = strV[:c.Flen]
		}
		casted = strV
	case mysql.TypeDecimal, mysql.TypeNewDecimal:
		switch v := val.(type) {
		case string:
			casted, err = mysql.ParseDecimal(v)
			if err != nil {
				err = newParseColError(err, c)
			}
		case int8:
			casted = mysql.NewDecimalFromInt(int64(v), 0)
		case int16:
			casted = mysql.NewDecimalFromInt(int64(v), 0)
		case int32:
			casted = mysql.NewDecimalFromInt(int64(v), 0)
		case int64:
			casted = mysql.NewDecimalFromInt(int64(v), 0)
//.........這裏部分代碼省略.........