I'm trying to delete documents whose value (timestamp) is past 2 hours. I have to call onSnapshot() but not snapshot.foreach() . Checked via console.log; Called1 shows up on the console, but Called2 doesn't. I'm wondering why it's not called to delete the document.
onMounted(() => {
const itemsCollectionRef = collection(db, "Bookings");
const cutoffTimestamp = Date.now() - 2 * 60 * 60 * 1000; // Two hours ago
const oldItemsQuery = query(
itemsCollectionRef,
where("Date", "<", cutoffTimestamp)
);
onSnapshot(oldItemsQuery, (snapshot) => {
console.log('called1');
snapshot.forEach((doc) => {
// Delete the document
console.log('called2');
db.collection("Bookings").doc(doc.id).delete();
});
});
}) 
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In Cloud Firestore, each field value is sorted in the index based on its value. In particular, numeric values are sorted earlier in the value index than
Timestampvalues. Your query forwhere("Date", "<", cutoffTimestamp)will always return 0 results because it is trying to findTimestampvalues that are less than the given number.To correct this problem, you need to pass a
TimestamporDatevalue to thewhere()filter. If you choose to use aDateobject, it will be automatically serialized by the SDK to a Timestamp object. This allows you to use what you feel comfortable with.const cutoffTimestamp = Timestamp.fromMillis(Date.now() - 2 * 60 * 60 * 1000); // Two hours ago // or const cutoffDate = new Date(Date.now() - 2 * 60 * 60 * 1000); const oldItemsQuery = query( itemsCollectionRef, where("Date", "Also, instead of recording "Bidding 1" and "Bidding 2", try the following:
onSnapshot(oldItemsQuery, (snapshot) => { console.log(`Found ${snapshot.size} documents older than 2h`); snapshot.forEach((doc) => { // Delete the document console.log(`Requesting #${doc.id} be deleted…`); deleteDoc(doc.ref) // console.log(`Deleted #${doc.id} successfully.`)) .catch((err) => console.error(`Failed to delete #${doc.id}`, err)); }); });