事务提交与回退

func startTxByDb(db * sql.DB){
                    var err       error
                    var result    sql.Result
                    var tx      * sql.Tx
                    var val1      int      = 10
                    var val2      string   = "hello"
                    var insertSQL string   = "insert into testcase1(col1, col2) values(:1, :2)"
                    //从连接池中开启一个事务
                    tx, err    = db.Begin()
                    getError(err)
                    result, err = tx.Exec(insertSQL, val1, val2)
                    if err != nil{
                            //事务回退
                            if rollbackErr := tx.Rollback(); rollbackErr != nil {
                                    log.Fatalf("unable to rollback: %b", rollbackErr)
                            }
                            log.Fatalln(err)
                            return
                    }
                    rowsAffected, err := result.RowsAffected()
                    getError(err)
                    fmt.Println(rowsAffected)
                    //事务提交
                    if err = tx.Commit(); err != nil {
                            log.Fatalln(err)
                    }
            }