type ExtractFunc struct {
	Timeword string       `parser:" \"EXTRACT\" \"(\" @( \"YEAR\":Timeword | \"MONTH\":Timeword | \"DAY\":Timeword | \"HOUR\":Timeword | \"MINUTE\":Timeword | \"SECOND\":Timeword | \"TIMEZONE_HOUR\":Timeword | \"TIMEZONE_MINUTE\":Timeword ) "`
	From     *PrimaryTerm `parser:" \"FROM\" @@ \")\" "`
}

// TrimFunc represents TRIM sql function
type TrimFunc struct {

		// do not convert to UTC, because we assume the user intends to encode
		// the date using the specified timezone. A user may want this control
		// because many legacy ZIP readers interpret the timestamp according
		// to the local timezone.
		//
		// The timezone is only non-UTC if a user directly sets the Modified
		// field directly themselves. All other approaches sets UTC.

)

var DB *gorm.DB
var (
	mysqlDSN     = "gorm:gorm@tcp(localhost:9910)/gorm?charset=utf8&parseTime=True&loc=Local"
	postgresDSN  = "user=gorm password=gorm dbname=gorm host=localhost port=9920 sslmode=disable TimeZone=Asia/Shanghai"
	sqlserverDSN = "sqlserver://gorm:LoremIpsum86@localhost:9930?database=gorm"
	tidbDSN      = "root:@tcp(localhost:9940)/test?charset=utf8&parseTime=True&loc=Local"
)

func init() {
	var err error

				Modified: time.Date(2011, 12, 8, 10, 4, 24, 0, timeZone(0)),
				Mode:     0666,
			},
			{
				Name:     "dir/bar",
				Content:  []byte("foo \r\n"),
				Modified: time.Date(2011, 12, 8, 10, 4, 50, 0, timeZone(0)),
				Mode:     0666,
			},
			{
				Name:     "dir/empty/",
				Content:  []byte{},
				Modified: time.Date(2011, 12, 8, 10, 8, 6, 0, timeZone(0)),
				Mode:     fs.ModeDir | 0777,
			},
			{

	//
	// When reading, an extended timestamp is preferred over the legacy MS-DOS
	// date field, and the offset between the times is used as the timezone.
	// If only the MS-DOS date is present, the timezone is assumed to be UTC.
	//
	// When writing, an extended timestamp (which is timezone-agnostic) is
	// always emitted. The legacy MS-DOS date field is encoded according to the
	// location of the Modified time.
	Modified time.Time

	timePartMonth          = "MONTH"
	timePartDay            = "DAY"
	timePartHour           = "HOUR"
	timePartMinute         = "MINUTE"
	timePartSecond         = "SECOND"
	timePartTimezoneHour   = "TIMEZONE_HOUR"
	timePartTimezoneMinute = "TIMEZONE_MINUTE"
)

func extract(what string, t time.Time) (v *Value, err error) {
	switch what {
	case timePartYear:
		return FromInt(int64(t.Year())), nil
	case timePartMonth:

)

// ISO8601Format converts time 't' into ISO8601 time format expected in AWS S3 spec.
//
// This function is needed to avoid a Go's float64 precision bug, where Go avoids
// padding the extra '0' before the timezone.
func ISO8601Format(t time.Time) string {
	value := t.Format(iso8601TimeFormat)
	if len(value) < len(iso8601TimeFormat) {
		value = t.Format(iso8601TimeFormat[:len(iso8601TimeFormat)-1])

		dst := filepath.Join(dstbase, pkgpath)
		src := filepath.Join(cwd, pkgpath)
		if err := copyLocalDir(dst, src); err != nil {
			return "", err
		}
	}

	if underGoRoot {
		// Copy timezone file.
		//
		// Typical apps have the zoneinfo.zip in the root of their app bundle,
		// read by the time package as the working directory at initialization.

	if !modified.IsZero() {
		f.Modified = modified.UTC()

		// If legacy MS-DOS timestamps are set, we can use the delta between
		// the legacy and extended versions to estimate timezone offset.
		//
		// A non-UTC timezone is always used (even if offset is zero).
		// Thus, FileHeader.Modified.Location() == time.UTC is useful for
		// determining whether extended timestamps are present.

		}
	}
}

func TestWriterTime(t *testing.T) {
	var buf bytes.Buffer
	h := &FileHeader{
		Name:     "test.txt",
		Modified: time.Date(2017, 10, 31, 21, 11, 57, 0, timeZone(-7*time.Hour)),
	}
	w := NewWriter(&buf)
	if _, err := w.CreateHeader(h); err != nil {
		t.Fatalf("unexpected CreateHeader error: %v", err)
	}
	if err := w.Close(); err != nil {