优化结构

pkg/database/migration/schema.go

@@ -0,0 +1,20 @@
+package migration
+
+import "gorm.io/gorm"
+
+// CreateMissingTables creates only schemas that are absent. Existing tables
+// are intentionally left untouched: GORM's MySQL column diff path can panic
+// when older servers return incomplete information_schema metadata, and this
+// project does not support implicit legacy-schema upgrades through AutoMigrate.
+func CreateMissingTables(db *gorm.DB, models ...any) error {
+	missing := make([]any, 0, len(models))
+	for _, model := range models {
+		if model != nil && !db.Migrator().HasTable(model) {
+			missing = append(missing, model)
+		}
+	}
+	if len(missing) == 0 {
+		return nil
+	}
+	return db.Migrator().CreateTable(missing...)
+}