I am facing a challenge with uploading a substantial data set from my node.js application to a mongodb. The process involves running a for loop to fetch each result. Initially, I established the connection to the MongoDB within every iteration of the loop, but this approach led to crashes.
After moving the connection setup outside the loop, encountering issues with db.close(). Leaving it inside the loop results in prematurely closing the connection, causing the app to crash with the error:
MongoError: server instance pool was destroyedHowever, when attempting to relocate the db.close() command outside the loop, it gets stuck and fails to exit the loop to proceed with subsequent operations.
I am seeking advice on how to efficiently close the database connection outside the for loop only upon completion of all iterations.
MongoClient.connect(url, function(err, db) {
if (err) throw err;
var dbo = db.db("mydatabase");
//execute SQL query to fetch data
for(result in sqldata) {
myobj = {Number: sqldata[result].Num} //<--- this for loop produces 16000 entries
dbo.collection("customers").insertOne(myobj, function(err, res) {
if (err) throw err;
console.log("1 document inserted");
db.close(); //<--- this is the issue
});
}
});