diff --git a/README.md b/README.md
index 4761845..2eacb6b 100644
--- a/README.md
+++ b/README.md
@@ -160,6 +160,8 @@ docker compose logs -f mediastation-go
 
 如果你确认以后不再使用 SQLite，也不希望应用再把旧 SQLite 当迁移源，可以这样做：
 
+> 只有在网页确认用户、媒体库、设置、媒体条目都已经出现在 PostgreSQL 后，才做下面这一步。
+
 ```yaml
 environment:
   MEDIASTATION_DATABASE_TYPE: postgres
diff --git a/README_EN.md b/README_EN.md
index b327b09..720d851 100644
--- a/README_EN.md
+++ b/README_EN.md
@@ -160,6 +160,8 @@ After you see `sqlite data migrated to postgres`, or after the web UI shows your
 
 To make the deployment PostgreSQL-only after migration, keep PostgreSQL selected and point the old SQLite migration path at a non-existent file:
 
+> Only do this after the web UI confirms that users, libraries, settings, and media rows are already present in PostgreSQL.
+
 ```yaml
 environment:
   MEDIASTATION_DATABASE_TYPE: postgres
diff --git a/internal/database/database.go b/internal/database/database.go
index 3b42c7d..09548c9 100644
--- a/internal/database/database.go
+++ b/internal/database/database.go
@@ -115,16 +115,13 @@ func MigrateSQLiteToCurrentIfNeeded(cfg *config.Config, target *gorm.DB, log *za
 	if cfg == nil || target == nil || target.Dialector == nil || target.Dialector.Name() != "postgres" {
 		return nil
 	}
-	sqlitePath := strings.TrimSpace(cfg.Database.DBPath)
+	sqlitePath, err := sqliteMigrationSourcePath(cfg, log)
+	if err != nil {
+		return err
+	}
 	if sqlitePath == "" {
 		return nil
 	}
-	if _, err := os.Stat(sqlitePath); err != nil {
-		if errors.Is(err, os.ErrNotExist) {
-			return nil
-		}
-		return fmt.Errorf("stat sqlite migration source: %w", err)
-	}
 	if complete, err := sqliteMigrationMarkedComplete(target); err != nil {
 		return err
 	} else if complete {
@@ -148,6 +145,9 @@ func MigrateSQLiteToCurrentIfNeeded(cfg *config.Config, target *gorm.DB, log *za
 	}
 
 	started := time.Now()
+	if err := resetBootstrapTargetBeforeSQLiteMigrationIfSafe(src, target, log); err != nil {
+		return err
+	}
 	copied, err := copyModelTables(src, target, 500)
 	if err != nil {
 		return err
@@ -164,6 +164,149 @@ func MigrateSQLiteToCurrentIfNeeded(cfg *config.Config, target *gorm.DB, log *za
 	return nil
 }
 
+func sqliteMigrationSourcePath(cfg *config.Config, log *zap.Logger) (string, error) {
+	configured := strings.TrimSpace(cfg.Database.DBPath)
+	if configured != "" {
+		exists, err := regularFileExists(configured)
+		if err != nil {
+			return "", fmt.Errorf("stat sqlite migration source: %w", err)
+		}
+		if exists {
+			return configured, nil
+		}
+	}
+
+	fallback := filepath.Join(strings.TrimSpace(cfg.App.DataDir), "mediastation.db")
+	if fallback == "" || sameCleanPath(configured, fallback) {
+		return "", nil
+	}
+	exists, err := regularFileExists(fallback)
+	if err != nil {
+		return "", fmt.Errorf("stat default sqlite migration source: %w", err)
+	}
+	if !exists {
+		return "", nil
+	}
+	if log != nil && configured != "" {
+		log.Warn("configured sqlite migration source not found; using data-dir default",
+			zap.String("configured", configured),
+			zap.String("fallback", fallback))
+	}
+	return fallback, nil
+}
+
+func regularFileExists(path string) (bool, error) {
+	if strings.TrimSpace(path) == "" {
+		return false, nil
+	}
+	info, err := os.Stat(path)
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			return false, nil
+		}
+		return false, err
+	}
+	return !info.IsDir(), nil
+}
+
+func sameCleanPath(a, b string) bool {
+	if a == "" || b == "" {
+		return false
+	}
+	return filepath.Clean(a) == filepath.Clean(b)
+}
+
+func resetBootstrapTargetBeforeSQLiteMigrationIfSafe(src, target *gorm.DB, log *zap.Logger) error {
+	hasRows, err := sqliteSourceHasMigratableRows(src)
+	if err != nil {
+		return err
+	}
+	if !hasRows {
+		return nil
+	}
+	bootstrapOnly, err := targetLooksLikeBootstrapOnly(target)
+	if err != nil || !bootstrapOnly {
+		return err
+	}
+	for i := len(model.AllModels()) - 1; i >= 0; i-- {
+		m := model.AllModels()[i]
+		if !target.Migrator().HasTable(m) {
+			continue
+		}
+		if err := target.Session(&gorm.Session{AllowGlobalUpdate: true}).Unscoped().Delete(m).Error; err != nil {
+			return fmt.Errorf("clear bootstrap target table %T: %w", m, err)
+		}
+	}
+	if log != nil {
+		log.Warn("cleared bootstrap postgres rows before sqlite migration")
+	}
+	return nil
+}
+
+func sqliteSourceHasMigratableRows(src *gorm.DB) (bool, error) {
+	for _, table := range []string{"users", "libraries", "media", "settings"} {
+		exists, err := sqliteTableExists(src, table)
+		if err != nil {
+			return false, err
+		}
+		if !exists {
+			continue
+		}
+		var count int64
+		if err := src.Raw("SELECT COUNT(1) FROM " + quoteIdent(table)).Scan(&count).Error; err != nil {
+			return false, fmt.Errorf("count sqlite table %s: %w", table, err)
+		}
+		if count > 0 {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+func targetLooksLikeBootstrapOnly(target *gorm.DB) (bool, error) {
+	for _, m := range []any{
+		&model.Library{},
+		&model.Series{},
+		&model.Media{},
+		&model.PlaybackHistory{},
+		&model.Favorite{},
+		&model.Playlist{},
+		&model.PlaylistItem{},
+		&model.DownloadTask{},
+		&model.Subscription{},
+	} {
+		if !target.Migrator().HasTable(m) {
+			continue
+		}
+		var count int64
+		if err := target.Unscoped().Model(m).Count(&count).Error; err != nil {
+			return false, err
+		}
+		if count > 0 {
+			return false, nil
+		}
+	}
+
+	var userCount int64
+	if !target.Migrator().HasTable(&model.User{}) {
+		return true, nil
+	}
+	if err := target.Model(&model.User{}).Count(&userCount).Error; err != nil {
+		return false, err
+	}
+	if userCount == 0 {
+		return true, nil
+	}
+	if userCount != 1 {
+		return false, nil
+	}
+	var user model.User
+	if err := target.Unscoped().Where("username = ?", "admin").First(&user).Error; err != nil {
+		return false, nil
+	}
+	return user.Role == "admin", nil
+}
+
 func sqliteMigrationMarkedComplete(db *gorm.DB) (bool, error) {
 	var value string
 	err := db.Raw("SELECT value FROM "+quoteIdent("settings")+" WHERE "+quoteIdent("key")+" = ?", sqliteMigrationCompleteSettingKey).Scan(&value).Error
@@ -513,6 +656,7 @@ func ensurePostgresColumnCompatibility(db *gorm.DB) error {
 	}
 	statements := []string{
 		`ALTER TABLE media ALTER COLUMN container TYPE varchar(128)`,
+		`ALTER TABLE media ALTER COLUMN genres TYPE text`,
 	}
 	for _, stmt := range statements {
 		if err := db.Exec(stmt).Error; err != nil {
diff --git a/internal/database/database_test.go b/internal/database/database_test.go
index bde9636..6e9fe87 100644
--- a/internal/database/database_test.go
+++ b/internal/database/database_test.go
@@ -1,12 +1,14 @@
 package database
 
 import (
+	"path/filepath"
 	"testing"
 	"time"
 
 	"github.com/glebarez/sqlite"
 	"gorm.io/gorm"
 
+	"github.com/ShukeBta/MediaStationGo/internal/config"
 	"github.com/ShukeBta/MediaStationGo/internal/model"
 )
 
@@ -149,6 +151,7 @@ func TestCopyModelTablesResumesPartialSQLiteMigration(t *testing.T) {
 		VideoCodec:   "hevc",
 		AudioCodec:   "eac3",
 		DurationSec:  120,
+		Genres:       "家庭,动画,冒险,喜剧,奇幻,Peter Del Vecho,Jeff Draheim,詹妮弗·李,克里斯·巴克,伊迪娜·门泽尔,克里斯汀·贝尔,乔什·盖德,乔纳森·格罗夫,埃文·蕾切尔·伍德,斯特林·K·布朗",
 		SizeBytes:    1024,
 		Width:        3840,
 		Height:       2160,
@@ -176,6 +179,9 @@ func TestCopyModelTablesResumesPartialSQLiteMigration(t *testing.T) {
 	if got.Container != media.Container {
 		t.Fatalf("container = %q, want %q", got.Container, media.Container)
 	}
+	if got.Genres != media.Genres {
+		t.Fatalf("genres = %q, want %q", got.Genres, media.Genres)
+	}
 
 	copied, err = copyModelTables(src, dst, 2)
 	if err != nil {
@@ -212,3 +218,87 @@ func TestSQLiteMigrationCompleteMarker(t *testing.T) {
 		t.Fatal("database should be marked migrated")
 	}
 }
+
+func TestSQLiteMigrationFallsBackToDataDirDefaultPath(t *testing.T) {
+	dir := t.TempDir()
+	sqlitePath := filepath.Join(dir, "mediastation.db")
+	src, err := gorm.Open(sqlite.Open(sqlitePath), &gorm.Config{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := src.AutoMigrate(&model.User{}, &model.Library{}); err != nil {
+		t.Fatal(err)
+	}
+	user := model.User{Username: "real-admin", PasswordHash: "hash", Role: "admin", IsActive: true}
+	if err := src.Create(&user).Error; err != nil {
+		t.Fatal(err)
+	}
+	lib := model.Library{Name: "Movies", Path: "/media/movies", Type: "movie", Enabled: true}
+	if err := src.Create(&lib).Error; err != nil {
+		t.Fatal(err)
+	}
+	sqlDB, _ := src.DB()
+	_ = sqlDB.Close()
+
+	dst, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := dst.AutoMigrate(&model.User{}, &model.Library{}, &model.Setting{}); err != nil {
+		t.Fatal(err)
+	}
+	if err := dst.Create(&model.User{Username: "admin", PasswordHash: "bootstrap", Role: "admin", IsActive: true}).Error; err != nil {
+		t.Fatal(err)
+	}
+
+	cfg := &config.Config{}
+	cfg.App.DataDir = dir
+	cfg.Database.DBPath = filepath.Join(dir, "disabled-sqlite-migration.db")
+	sourcePath, err := sqliteMigrationSourcePath(cfg, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if sourcePath != sqlitePath {
+		t.Fatalf("source path = %q, want fallback %q", sourcePath, sqlitePath)
+	}
+
+	src2, err := gorm.Open(sqlite.Open(sourcePath), &gorm.Config{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	sqlDB2, _ := src2.DB()
+	defer func() {
+		if sqlDB2 != nil {
+			_ = sqlDB2.Close()
+		}
+	}()
+	if err := resetBootstrapTargetBeforeSQLiteMigrationIfSafe(src2, dst, nil); err != nil {
+		t.Fatal(err)
+	}
+	copied, err := copyModelTables(src2, dst, 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if copied != 2 {
+		t.Fatalf("copied rows = %d, want 2", copied)
+	}
+
+	var userCount int64
+	if err := dst.Model(&model.User{}).Count(&userCount).Error; err != nil {
+		t.Fatal(err)
+	}
+	if userCount != 1 {
+		t.Fatalf("user count = %d, want migrated source only", userCount)
+	}
+	var got model.User
+	if err := dst.First(&got, "username = ?", "real-admin").Error; err != nil {
+		t.Fatal(err)
+	}
+	var libCount int64
+	if err := dst.Model(&model.Library{}).Where("path = ?", "/media/movies").Count(&libCount).Error; err != nil {
+		t.Fatal(err)
+	}
+	if libCount != 1 {
+		t.Fatalf("library count = %d, want 1", libCount)
+	}
+}
diff --git a/internal/model/model.go b/internal/model/model.go
index 45f9b86..c7f0b9f 100644
--- a/internal/model/model.go
+++ b/internal/model/model.go
@@ -95,7 +95,7 @@ type Media struct {
 	TheTVDBID    string  `gorm:"column:thetvdb_id;size:64" json:"thetvdb_id,omitempty"`
 	Languages    string  `gorm:"size:64"  json:"languages,omitempty"` // 逗号分隔的 ISO 639-1 代码，如 "zh,en"
 	Countries    string  `gorm:"size:128" json:"countries,omitempty"` // 逗号分隔的 ISO 3166-1，如 "CN,US"
-	Genres       string  `gorm:"size:255" json:"genres,omitempty"`    // 逗号分隔的类型名，如 "Action,Animation"
+	Genres       string  `gorm:"type:text" json:"genres,omitempty"`   // 逗号分隔的类型名，如 "Action,Animation"
 	NSFW         bool    `gorm:"default:false" json:"nsfw"`
 
 	// STRMURL is the indirection target for .strm files: when present the