// create a new gorm.DB instance db, err := gorm.Open("sqlite3", "test.db") if err != nil { panic("failed to connect database") } // start a transaction tx := db.Begin() // perform a database operation that might fail result := tx.Where("name = ?", "John").First(&User{}) // check for errors if result.Error != nil { // add additional error information to the transaction tx.AddError(fmt.Errorf("error querying user: %s", result.Error)) // rollback the transaction tx.Rollback() // handle the error log.Fatal(result.Error) } // commit the transaction err = tx.Commit().Error if err != nil { log.Fatal("error committing transaction: ", err) }In this example, we create a new gorm.DB instance and begin a transaction. We then perform a database operation that might fail (attempting to find a user with the name "John"). If the operation fails, we use tx.AddError to add additional error information to the transaction and then rollback the transaction. If the operation succeeds, we commit the transaction. Note that AddError does not actually return an error. Instead, it adds the error to the transaction and continues processing.