使用inedx索引获取数据，事务被打断？

 <script type="text/javascript">
        var myDB = indexedDB.open("myDB", 1);

        myDB.onupgradeneeded = function (e) {
            console.log(myDB);
            var db = e.target.result;
            var myStore = null;
            console.log(db);
            if (!db.objectStoreNames.contains("myStore")) {
                myStore = db.createObjectStore("myStore", {
                    autoIncrement: true,
                })
            }
            myStore.createIndex("myStore", "name", {
                unique: true,
            })
        }
        var data = [{
            "name": "alex",
            "age": "18"
        }, {
            "name": "manfrend",
            age: "20"
        }, {
            "name": "leo",
            "age": "21",
        }]
        setTimeout(function () {
            var db = myDB.result;

            var transaction = db.transaction("myStore", "readwrite");
            var store = transaction.objectStore("myStore");
            for (let i = 0; i < data.length; i++) {
                store.put(data[i]);
            }
            var index = store.index("myStore");
            index.get("alex").onerror = function (e) {
                console.log(e);

            }
            index.get("alex").onsuccess = function (e) {
                console.log(e);

            }

        }, 300)
    </script>

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