The auto-commit principle of transactions has an interesting side effect. During a transaction, we cannot introduce an async operation like fetch or
setTimeout. IndexedDB does not hold the transaction until these reach completion. This process is especially noticeable when using fetch and
setTimeout combined with an IndexedDB transaction. The IndexedDB spec's authors feel that transactions should be short-lived. Primarily for reasons of performance.
Readwrite transactions, in particular, "
lock" the stores for writing. So, if one part of the program initiates readwrite on the books object store, another portion of the application that wishes to do the same must wait: the new transaction "
hangs" until the previous one reaches completion. If transactions take a long time, this might cause unusual delays.
Code Example :
let request1 = books.add(book);
request1.onsuccess = function () {
fetch('/').then((response) => {
let request2 = books.add(anotherBook); // (*)
request2.onerror = function () {
console.log(request2.error.name); // TransactionInactiveError
};
});
};?
