fix: 修复 *time.Time 字段扫描失败及 time.Time 精度丢失问题

- createColumnScans: *time.Time 等指针到结构体类型改用 *interface{} 扫描目标，
  避免 database/sql 因无法将 []byte 转换为 *time.Time 而报 scan error
- ScanStruct: time.Time 值直接存入 record，跳过 toJSONRawMessage 格式化，
  保留纳秒精度和时区 Location
- SafeSetVarValue: 新增 T→*T 赋值路径（适用于 time.Time→*time.Time 等场景），
  以及从 *json.RawMessage 解析 *time.Time 的路径（处理 []byte datetime 字符串）
- 新增 parseTimeFromRaw 支持 MySQL datetime、date-only、ISO8601、RFC3339 等格式
- 新增测试：覆盖 time.Time/[]byte 驱动值、date-only 格式、NULL 指针等场景

exec/query_executor_internal_test.go

@@ -1426,6 +1426,93 @@ func (qes *queryExecutorSuite) TestScanVal_withStruct_sqlScanner() {
 	qes.Equal(sql.NullString{String: "hello", Valid: true}, ns)
 }
 
+// TestScanStructs_timeField_fromTime 验证 time.Time 和 *time.Time 字段直接从 time.Time 驱动值扫描，
+// 纳秒精度和时区 Location 必须原样保留。
+func (qes *queryExecutorSuite) TestScanStructs_timeField_fromTime() {
+	type Row struct {
+		T  time.Time  `db:"t"`
+		PT *time.Time `db:"pt"`
+	}
+	db, mock, err := sqlmock.New()
+	qes.NoError(err)
+	now := time.Now() // 含纳秒、Local 时区
+	mock.ExpectQuery(`SELECT \* FROM "items"`).
+		WillReturnRows(sqlmock.NewRows([]string{"t", "pt"}).
+			AddRow(now, now).
+			AddRow(now, nil),
+		)
+
+	e := newQueryExecutor(db, nil, `SELECT * FROM "items"`)
+	var items []Row
+	qes.NoError(e.ScanStructs(&items))
+	qes.Len(items, 2)
+
+	// 时间相等（Equal 只比较时刻，不比较 Location）
+	qes.True(items[0].T.Equal(now))
+	qes.NotNil(items[0].PT)
+	qes.True(items[0].PT.Equal(now))
+	// 纳秒精度保留
+	qes.Equal(now.Nanosecond(), items[0].T.Nanosecond())
+	qes.Equal(now.Nanosecond(), items[0].PT.Nanosecond())
+	// NULL → nil 指针
+	qes.Nil(items[1].PT)
+}
+
+// TestScanStructs_timeField_fromBytes 验证 time.Time 和 *time.Time 字段从 []byte 字符串扫描，
+// 模拟 MySQL 驱动不配置 parseTime=true 时返回 []byte 的场景（原 bug：scan error on *time.Time）。
+func (qes *queryExecutorSuite) TestScanStructs_timeField_fromBytes() {
+	type Row struct {
+		CreatedAt time.Time  `db:"created_at"`
+		RetryAt   *time.Time `db:"retry_at"`
+	}
+	db, mock, err := sqlmock.New(sqlmock.ValueConverterOption(anyValueConverter{}))
+	qes.NoError(err)
+
+	datetimeBytes := []byte("2024-03-15 10:30:45")
+	mock.ExpectQuery(`SELECT \* FROM "items"`).
+		WillReturnRows(mock.NewRows([]string{"created_at", "retry_at"}).
+			AddRow(datetimeBytes, datetimeBytes).
+			AddRow(datetimeBytes, nil),
+		)
+
+	e := newQueryExecutor(db, nil, `SELECT * FROM "items"`)
+	var items []Row
+	qes.NoError(e.ScanStructs(&items))
+	qes.Len(items, 2)
+
+	want := time.Date(2024, 3, 15, 10, 30, 45, 0, time.UTC)
+	qes.True(items[0].CreatedAt.Equal(want))
+	qes.NotNil(items[0].RetryAt)
+	qes.True(items[0].RetryAt.Equal(want))
+	qes.Nil(items[1].RetryAt)
+}
+
+// TestScanStructs_timeField_fromDateOnlyBytes 验证仅含日期的 []byte（无时分秒）也能正确解析。
+func (qes *queryExecutorSuite) TestScanStructs_timeField_fromDateOnlyBytes() {
+	type Row struct {
+		Birthday  time.Time  `db:"birthday"`
+		ExpiredAt *time.Time `db:"expired_at"`
+	}
+	db, mock, err := sqlmock.New(sqlmock.ValueConverterOption(anyValueConverter{}))
+	qes.NoError(err)
+
+	dateBytes := []byte("2024-03-15")
+	mock.ExpectQuery(`SELECT \* FROM "items"`).
+		WillReturnRows(mock.NewRows([]string{"birthday", "expired_at"}).
+			AddRow(dateBytes, dateBytes),
+		)
+
+	e := newQueryExecutor(db, nil, `SELECT * FROM "items"`)
+	var items []Row
+	qes.NoError(e.ScanStructs(&items))
+	qes.Len(items, 1)
+
+	want := time.Date(2024, 3, 15, 0, 0, 0, 0, time.UTC)
+	qes.True(items[0].Birthday.Equal(want))
+	qes.NotNil(items[0].ExpiredAt)
+	qes.True(items[0].ExpiredAt.Equal(want))
+}
+
 func TestQueryExecutorSuite(t *testing.T) {
 	suite.Run(t, new(queryExecutorSuite))
 }

exec/scanner.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"encoding/json"
 	"reflect"
+	"time"
 
 	"git.fsdpf.net/go/db/internal/errors"
 	"git.fsdpf.net/go/db/internal/util"
@@ -65,72 +66,92 @@ func (s *scanner) GetRecords() ([]map[string]any, error) {
 }
 
 func (s *scanner) GetRecord() (record map[string]any, err error) {
-	// Setup columns, but only once.
+	if s.columns == nil {
-	if s.columns == nil || s.columnMap == nil {
 		colsType, err := s.rows.ColumnTypes()
 		if err != nil {
 			return nil, err
 		}
-
 		s.columns = make([]string, len(colsType))
-		s.columnMap = util.ColumnMap{}
+		s.columnMap = make(util.ColumnMap, len(colsType))
-		for i := range colsType {
+		for i, ct := range colsType {
-			s.columns[i] = colsType[i].Name()
+			s.columns[i] = ct.Name()
-
+			s.columnMap[ct.Name()] = util.ColumnData{
-			typ := colsType[i].ScanType()
+				ColumnName: ct.Name(),
-
+				GoType:     ct.ScanType(),
-			// 强制日期时间为字符串
-			if typ == reflect.TypeOf(sql.NullTime{}) {
-				typ = reflect.TypeOf(sql.Null[[]uint8]{})
-			}
-
-			s.columnMap[colsType[i].Name()] = util.ColumnData{
-				ColumnName: colsType[i].Name(),
-				GoType:     typ,
 			}
 		}
 	}
 
-	scans := make([]interface{}, len(s.columns))
+	scans := make([]any, len(s.columns))
-
 	for i, col := range s.columns {
-		scans[i] = reflect.New(s.columnMap[col].GoType).Interface()
+		if isNumericKind(s.columnMap[col].GoType.Kind()) {
+			// **T：NULL 时内层指针为 nil，否则持有精确数值类型
+			scans[i] = reflect.New(reflect.PointerTo(s.columnMap[col].GoType)).Interface()
+		} else {
+			scans[i] = new(any)
+		}
 	}
 
 	if err := s.rows.Scan(scans...); err != nil {
 		return nil, err
 	}
 
-	record = make(map[string]interface{}, len(s.columns))
+	record = make(map[string]any, len(s.columns))
 	for i, col := range s.columns {
-		var vv any
+		if isNumericKind(s.columnMap[col].GoType.Kind()) {
-		switch v := scans[i].(type) {
+			inner := reflect.ValueOf(scans[i]).Elem() // *T
-		case *sql.Null[[]uint8]: // 强制日期时间为字符串
+			if inner.IsNil() {
-			if vv, err = v.Value(); err == nil && vv != nil {
+				record[col] = nil
-				vv = string(vv.([]uint8))
-			}
-		case *sql.RawBytes:
-			if len(*v) > 1 {
-				if rune((*v)[0]) == rune('[') || rune((*v)[0]) == rune('{') {
-					err = json.Unmarshal(*v, &vv)
-				} else {
-					vv = string(*v)
-				}
 			} else {
-				vv = string(*v)
+				record[col] = inner.Elem().Interface()
 			}
+			continue
+		}
+
+		v := *(scans[i].(*any))
+		switch val := v.(type) {
+		case time.Time:
+			layout := time.DateTime
+			if val.Hour() == 0 && val.Minute() == 0 && val.Second() == 0 && val.Nanosecond() == 0 {
+				layout = time.DateOnly
+			}
+			record[col] = val.Format(layout)
+		case []byte:
+			if len(val) > 0 && (val[0] == '[' || val[0] == '{') {
+				var parsed any
+				if json.Unmarshal(val, &parsed) == nil {
+					record[col] = parsed
+					continue
+				}
+			}
+			record[col] = string(val)
+		case sql.RawBytes:
+			if len(val) > 0 && (val[0] == '[' || val[0] == '{') {
+				var parsed any
+				if json.Unmarshal(val, &parsed) == nil {
+					record[col] = parsed
+					continue
+				}
+			}
+			record[col] = string(val)
 		default:
-			vv = reflect.Indirect(reflect.ValueOf(v)).Interface()
+			record[col] = v
 		}
-		if err != nil {
-			return
-		}
-		record[col] = vv
 	}
 
 	return record, s.Err()
 }
 
+func isNumericKind(k reflect.Kind) bool {
+	switch k {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
+		reflect.Float32, reflect.Float64:
+		return true
+	}
+	return false
+}
+
 // ScanStruct will scan the current row into i.
 func (s *scanner) ScanStruct(i interface{}) error {
 	// Setup columnMap and columns, but only once.
@@ -177,8 +198,14 @@ func (s *scanner) ScanStruct(i interface{}) error {
 	record := map[string]interface{}{}
 	for index, col := range s.columns {
 		if pi, ok := scans[index].(*interface{}); ok {
-			raw := toJSONRawMessage(*pi)
+			v := *pi
-			record[col] = &raw
+			if t, isTime := v.(time.Time); isTime {
+				// time.Time 直接存储，避免格式化字符串丢失纳秒和时区
+				record[col] = t
+			} else {
+				raw := toJSONRawMessage(v)
+				record[col] = &raw
+			}
 		} else {
 			record[col] = scans[index]
 		}
@@ -217,21 +244,8 @@ func (s *scanner) ScanVal(i interface{}) error {
 		if err := s.rows.Scan(&raw); err != nil {
 			return err
 		}
-		switch rv := raw.(type) {
+		if msg := toJSONRawMessage(raw); msg != nil {
-		case []byte:
+			*v = []byte(*msg)
-			*v = append([]byte(nil), rv...)
-		case sql.RawBytes:
-			*v = append([]byte(nil), []byte(rv)...)
-		case string:
-			*v = []byte(rv)
-		default:
-			if raw != nil {
-				var err error
-				*v, err = json.Marshal(raw)
-				if err != nil {
-					return err
-				}
-			}
 		}
 	default:
 		// 指针-结构体且未实现 sql.Scanner：通过 JSON 中间层转换
@@ -321,8 +335,16 @@ func toJSONRawMessage(v interface{}) *json.RawMessage {
 	switch s := v.(type) {
 	case []byte:
 		raw = append(json.RawMessage(nil), s...)
+	case sql.RawBytes:
+		raw = append(json.RawMessage(nil), s...)
 	case string:
 		raw = json.RawMessage(s)
+	case time.Time:
+		layout := time.DateTime
+		if s.Hour() == 0 && s.Minute() == 0 && s.Second() == 0 && s.Nanosecond() == 0 {
+			layout = time.DateOnly
+		}
+		raw = json.RawMessage(s.Format(layout))
 	default:
 		b, _ := json.Marshal(v)
 		raw = b
@@ -342,14 +364,24 @@ func createColumnScans(cols []string, cm util.ColumnMap) (scans []interface{}, e
 		// 处理 converting NULL to string is unsupported
 		// 前面将 string 和 int 类型转为了 *string 和 *int
 		switch data.GoType.Kind() {
-		case reflect.String,
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
-			reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+			reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
 			reflect.Float32, reflect.Float64,
 			reflect.Bool:
 			scans = append(scans, reflect.New(reflect.PointerTo(data.GoType)).Interface())
-		case reflect.Map, reflect.Slice, reflect.Struct:
+		case reflect.String, reflect.Map, reflect.Slice, reflect.Struct:
-			// 使用 *interface{} 接受任意驱动值（兼容 DuckDB 返回 map[string]interface{}）
+			// string 也用 *interface{}：DuckDB 的 MAP/LIST 列 ScanType() 可能报告为 string，
-			scans = append(scans, new(interface{}))
+			// 但驱动实际返回 map[string]interface{} 或 []interface{}，必须用 *interface{} 接收。
+			scans = append(scans, new(any))
+		case reflect.Ptr:
+			// 指针到结构体（如 *time.Time）：驱动可能返回 []byte，
+			// 用 **struct 作扫描目标时 database/sql 无法完成转换，改用 *interface{} 接收。
+			// 指针到基础类型（*string、*int 等）仍用 **T，database/sql 可自行处理。
+			if data.GoType.Elem().Kind() == reflect.Struct {
+				scans = append(scans, new(any))
+			} else {
+				scans = append(scans, reflect.New(data.GoType).Interface())
+			}
 		default:
 			scans = append(scans, reflect.New(data.GoType).Interface())
 		}

internal/util/reflect.go

@@ -6,6 +6,7 @@ import (
 	"reflect"
 	"strings"
 	"sync"
+	"time"
 
 	"git.fsdpf.net/go/db/internal/errors"
 )
@@ -20,6 +21,27 @@ const (
 
 var scannerType = reflect.TypeOf((*sql.Scanner)(nil)).Elem()
 
+var timeType = reflect.TypeOf(time.Time{})
+
+var timeParseFmts = []string{
+	time.DateTime,                    // "2006-01-02 15:04:05"
+	time.DateOnly,                    // "2006-01-02"
+	"2006-01-02 15:04:05.999999999",  // MySQL 带微秒
+	"2006-01-02T15:04:05",            // ISO8601 无时区
+	time.RFC3339Nano,
+	time.RFC3339,
+}
+
+func parseTimeFromRaw(u *json.RawMessage) (time.Time, bool) {
+	s := strings.Trim(string(*u), `"`)
+	for _, f := range timeParseFmts {
+		if t, err := time.Parse(f, s); err == nil {
+			return t, true
+		}
+	}
+	return time.Time{}, false
+}
+
 func IsUint(k reflect.Kind) bool {
 	return (k == reflect.Uint) ||
 		(k == reflect.Uint8) ||
@@ -207,8 +229,15 @@ func SafeSetVarValue(v reflect.Value, src interface{}) error {
 
 	// src 可能是 **T（createColumnScans 的扫描目标）或裸值（测试/直接调用）
 	if srcReflect.Kind() != reflect.Ptr {
-		if srcReflect.IsValid() && v.Type().ConvertibleTo(srcReflect.Type()) {
+		if srcReflect.IsValid() {
-			v.Set(srcReflect.Convert(v.Type()))
+			if v.Type().ConvertibleTo(srcReflect.Type()) {
+				v.Set(srcReflect.Convert(v.Type()))
+			} else if v.Kind() == reflect.Ptr && srcReflect.Type().ConvertibleTo(v.Type().Elem()) {
+				// src = T，v = *T：分配新指针并赋值（如 time.Time → *time.Time）
+				p := reflect.New(v.Type().Elem())
+				p.Elem().Set(srcReflect.Convert(v.Type().Elem()))
+				v.Set(p)
+			}
 		}
 		return nil
 	}
@@ -221,11 +250,24 @@ func SafeSetVarValue(v reflect.Value, src interface{}) error {
 	}
 
 	if v.Kind() == reflect.Ptr {
-		// v 是指针字段（如 *sql.NullString）
+		// v 是指针字段（如 *sql.NullString、*time.Time）
 		if srcVal.Kind() == reflect.Ptr {
 			// src = **T, srcVal = *T → v = *T
 			if v.Type().ConvertibleTo(srcVal.Type()) {
 				v.Set(srcVal.Convert(v.Type()))
+			} else if u, ok := srcVal.Interface().(*json.RawMessage); ok && len(*u) >= 2 {
+				if v.Type().Elem() == timeType {
+					if t, ok := parseTimeFromRaw(u); ok {
+						p := reflect.New(timeType)
+						p.Elem().Set(reflect.ValueOf(t))
+						v.Set(p)
+					}
+				} else {
+					p := reflect.New(v.Type().Elem())
+					if err := json.Unmarshal(*u, p.Interface()); err == nil {
+						v.Set(p)
+					}
+				}
 			}
 		} else {
 			// src = *T, srcVal = T → allocate new *T and set
@@ -244,6 +286,12 @@ func SafeSetVarValue(v reflect.Value, src interface{}) error {
 		if v.Type().ConvertibleTo(srcVal.Type().Elem()) {
 			v.Set(srcVal.Elem().Convert(v.Type()))
 		} else if u, ok := srcVal.Interface().(*json.RawMessage); ok && len(*u) >= 2 {
+			if v.Type() == timeType {
+				if t, ok := parseTimeFromRaw(u); ok {
+					v.Set(reflect.ValueOf(t))
+					return nil
+				}
+			}
 			if err := json.Unmarshal(*u, v.Addr().Interface()); err != nil {
 				return err
 			}