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Ponu Maurya

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"Ponnu bio" likely refers to information about someone named Ponnu, or the scientific name of a plant. Based on the search results, "Ponnu" can be a name, a nickname, or a scientific name for a plant. It can also be used in relation to business, or even refer to a type of bio.

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Ponu Maurya

Ponu Maurya

06-Jul-2025

If a transaction in IndexedDB is not completed successfully, it has significant consequences, including data loss, inconsistent state, or silent failures that may be hard to debug.

Risks of Not Completing a Transaction

Risk What Happens
No oncomplete Changes might not be written; browser may roll back
Uncaught error Entire transaction rolls back (nothing is saved)
Async delay or await inside transaction Transaction auto-closes before write — results in TransactionInactiveError
Not handling onerror or onabort You lose track of failures — app silently breaks

Example of a Failed Write

const tx = db.transaction("notes", "readwrite");
const store = tx.objectStore("notes");

store.put({ id: 1, content: "Note" });

// No error handling:
setTimeout(() => {
  // This fails because the transaction auto-closed
  store.put({ id: 2, content: "Late Note" }); // ❌ TransactionInactiveError
}, 100);

How to Handle Failed Writes Properly

1. Use try/catch with Promises

try {
  const tx = db.transaction(["users", "notes"], "readwrite");
  tx.objectStore("users").put({ id: "u1", name: "Alice" });
  tx.objectStore("notes").put({ id: "n1", userId: "u1", content: "Welcome!" });

  await new Promise((resolve, reject) => {
    tx.oncomplete = resolve;
    tx.onerror = () => reject(tx.error);
    tx.onabort = () => reject(tx.error);
  });

  console.log("Transaction successful.");
} catch (err) {
  console.error("Transaction failed and rolled back:", err);
}

2. Handle Transaction Events: oncomplete, onerror, onabort

const tx = db.transaction("notes", "readwrite");

tx.oncomplete = () => console.log("Success ✅");
tx.onerror = () => console.error("Error ❌", tx.error);
tx.onabort = () => console.warn("Aborted 🛑", tx.error);

3. Avoid Delays During a Transaction

Don’t do async work inside the transaction, or it may auto-close:

// ❌ Bad: async code inside transaction scope
const tx = db.transaction("notes", "readwrite");
await fetch("/api/data"); // this yields the event loop
tx.objectStore("notes").put({ ... }); // ❌ TransactionInactiveError

✅ Instead:

const data = await fetch("/api/data").then(res => res.json());
const tx = db.transaction("notes", "readwrite");
tx.objectStore("notes").put(data);

4. Recover from Failures

If a write fails:

  • Log the error or show a user notification
  • Optionally retry the transaction
  • Store in a local queue for background sync
if (tx.error?.name === "QuotaExceededError") {
  alert("Storage is full. Please clear space.");
}

Summary: Preventing Transaction Failure

Best Practice Benefit
Handle onerror, onabort, oncomplete Know exactly what happened
Wrap in try/catch if using async Catch errors in one place
Avoid async delays in transaction Prevent TransactionInactiveError
Confirm success via oncomplete Ensure all writes finished
Log and retry failed writes Improve user experience

 

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