I have a sqlite database and with the programm sqliteStudio I can connect and save things. My Problem is the connection to the database with node.js with the npm package "sqlite". Every time I want to do a query it can't find the table. My code:
const connection = await sqlite.open('./db.sqlite');
const data = await connection.run("select * from item")
After that with console.log(connection), I get the following message with looks good in my opinion
driver: Database { open: true, filename: './db.sqlite', mode: 65542 },
Promise: [Function: Promise] }
But the output of console.log(data) is always a error message:
{ Error: SQLITE_ERROR: no such table: item errno: 1, code: 'SQLITE_ERROR' }
I think it is a problem with async/await or with my .sqlite file but I don't know
you are right, you have to use the arrow-function to wait until database is open, see here:
// database is not existing
console.log('open database and create table');
db = new sqlite3.Database('./event.db',() => {
db.run('CREATE TABLE logTable(logfile TEXT,logdate TEXT,referto TEXT, area TEXT,status TEXT,action TEXT)',() => {
...
});
// if db is existing
db = new sqlite3.Database('./event.db'() => {
...
});
Related
I wanna create a hook function when client search any query in database and tried to use Mongo.watch()
Reference code:
mongo.db
.watch([{ $match: { operationType: 'insert' } }])
.on("change", (next) => {
console.log("##", next);
});
It is working when I using .insert() and .update(), as I know that is working for data changed but not for .find().
How can i hook query after find?
I found the solution finally and mark down the code base here.
Mongo.watch() only notifies on data changes that have persisted to a majority of data-bearing members as the document (update, delete, insert).
Try to use Command Monitoringto monitor the success or failure of commands sent to Mongo Database.
Example:
const { MongoClient } = require("mongodb");
const mongo_client = new MongoClient("mongodb://localhost", { monitorCommands:true });
mongo_client.on('commandStarted', (event) => {
if(["find", "aggregate"].includes(event.commandName)){
console.log({
requestId: event.requestId,
database: event.databaseName,
commanName: event.commandName,
collection: (event.commandName=="find")? event.command.find : event.command.aggregate,
query: (event.commandName=="find")? event.command.filter : event.command.pipeline
})
}
})
mongo_client.on('commandStarted', (event) => {
if(["find", "aggregate"].includes(event.commandName)){
console.log({
requestId: event.requestId,
result: event.reply.cursor.firstBatch
})
}
})
I'm new to Node, along with Mongoose and MongoDB. I'm trying to test inserting data into one of the collections in a database on MongoDB Atlas. However, the code somehow inserts the data into the wrong database. I intend to insert data into the 'test' collection in the 'quizzard' database. However, a new collection called 'tests' was created within quizzard where the data was placed. When I tried it again, it started inserting data into another database called 'test' and created a collection called 'tests', where the data is still being placed.
var link = "mongodb+srv://<user>:<password>#quizzard-dp0b2.mongodb.net/test?retryWrites=true&w=majority";
// changed to <user> and <password> for privacy reasons
mongoose.connect(link, {
useNewUrlParser: true,
useUnifiedTopology: true
});
mongoose.connection.on('connected', () => {
console.log('Connected');
});
const Schema = mongoose.Schema;
const TestSchema = new Schema({
_id: Number,
data: String
});
//TestSchema.set('database', 'test');
//TestSchema.set('collection', 'test');
const Test = mongoose.model('Test', TestSchema);
const data = {
_id: 11,
data: "why???"
};
const newTest = new Test(data);
newTest.save((error) => {
if(error){
console.log("An error has occured");
} else {
console.log("Action performed");
}
});
You need to change the link; after the first slash, you choose which DB you want to use.
Examples
// DB NAME youinsertinheredbname
var link = "mongodb+srv://<user>:<password>#quizzard-dp0b2.mongodb.net/youinsertinheredbname?retryWrites=true&w=majority";
// DB NAME stackoverflow
var link = "mongodb+srv://<user>:<password>#quizzard-dp0b2.mongodb.net/stackoverflow?retryWrites=true&w=majority";
I have a program that receive a New file from FTP server after some specific time , I insert the new updated file's data into my database MongoDB the fields remain same , only data changes in new file.. Now the problem is that EVERY TIME I have to insert whole new collection into database, and the collection increases accordingly.Forexample- first time data is of 20 records , second time 40 and then 60 and so on .The thing I want to do is I want to check which field's data is updated in New file before inserting new FILE's data , and should only update these field's data in database instead of inserting whole new document.Does MONGOOSE or MONGODB provide solution for this , means IF I PASS A DATA AS PARAMETER , IT SOULD COMPARE MY EXISTING COLLECTION WITH MY NEW DATA and then Update Only UPDATED FIELDS ..Please help me i,m stuck , thanks :) . I,m using NODE JS ...
var c = new Client();
var connectionProperties = {
host: 'ABC',
user: 'ABC',
port: 'ABC',
password: 'ABC',
};
c.connect(connectionProperties);
c.on('ready', function () {
c.get('path-to-excel-file', function (err, stream) {
if (err) throw err;
stream.once('close', function () {
const workBook = XLSX.readFile('Convertedfile.xlsx');
XLSX.writeFile(workBook, 'Convertedfile', { bookType: "csv" });
csv()
.fromFile("Convertedfile")
.then((jsonObj) => {
Model.collection.insert(jsonObj, function (err, docs) {
if (err) {
return console.error(err);
} else {
console.log("All Documents insterted");
}
});
})
c.end()
});
stream.pipe(fs.createWriteStream('ConvertedFile.xlsx'))
})
})
It looks like you need upsert means update if document/record exists or insert/create it.
So this can be done either 1 document at a moment or in bulk, but it would need a query to find the matching document(s) first.
Since you've not provided any sample data so I can't write a sample code snippet for you but here is the link to get you started, for bulk: Bulk.find.upsert and for single document this thread is good : how-do-i-update-upsert-a-document-in-mongoose
Update: here is the mongodb bulk upsert in action:
const mongo = require('mongodb');
const MongoClient = mongo.MongoClient;
const client = new MongoClient('mongodb://127.0.0.1:27017', { useUnifiedTopology: true });
client.connect(async err => {
if (err) {
console.log('DB Connection Error ', err);
} else {
const db = client.db('node-cheat-db');
// lets assume you've read all file contents and data is now ready for db operation
let records = [
{first: 'john', last: 'doe', email: 'johen#doe.com'},
{first: 'jack', last: 'doe', email: 'jack#doe.com'},
{first: 'jill', last: 'doe_updated', email: 'jill#doe.com'}
];
// prepare bulk upsert so that new records are created and existing are updated
let bulk = db.collection('users').initializeOrderedBulkOp();
for (var i = 0; i < records.length; i++) {
bulk.find({
"email": records[i].email // at least 1 key should be treated as PK; in this example email is PK
}).upsert(records[i]).replaceOne(records[i]);
}
bulk.execute(function (err,updateResult) {
if (updateResult.result.ok != 1) {
console.log('Bulk Upsert Error');
} else {
console.log(`Inserted: ${updateResult.result.nUpserted} and Updated: ${updateResult.result.nModified}`);
}
});
}
});
sample output looks like:
Inserted: 0 and Updated: 3
Further Details:
Clone node-cheat bulk-update, run node bulk-update.js followed by npm install mongodb.
There is a code:
const { MongoClient } = require('mongodb')
const db = MongoClient.connect('mongodb://172.17.0.2:27017/test')
db
.then(
async dataBase => {
eduDb = dataBase.db('edu-service-accounts')
const accounts = eduDb.collection('accounts')
await accounts.createIndex({ email: 1 }, { unique: true })
accounts.insertOne({ email: '123' })
}
)
Code above creates an index, but that is no unique. I already read official docs for native mongoDB driver, but can't handle it.
And yes, I've deleted all old indexex before testing that code.
Can someone please show a code that really create an index with unique.
I mean not part of official doc, or something like that - I need code that works.
NOTE: I tested that code with local db and mlab - the same result.
Like the documentation says: db.createIndex(collectionname, index[, options], callback) the creation returns an index. Try to log the result of the callback. Maybe you are getting an error from the db.
Try something like:
// your connection stuff
accounts.createIndex({ email: 1 }, { unique: true }, function(err, result) {
if(err) {
console.log(err);
} else {
console.log(result);
}
});
After that please provide us the logs.
There are some similar questions but all of them involves using the MongoDB NodeJS driver instead of Mongoose ODM.
I read the docs but couldn't find such functionality.
You can't directly get the list from the connection provided by mongoose, but it's easy to do with the mongo Admin object as it contains a function called listDatabases:
var mongoose = require('mongoose')
, Admin = mongoose.mongo.Admin;
/// create a connection to the DB
var connection = mongoose.createConnection(
'mongodb://user:pass#localhost:port/database');
connection.on('open', function() {
// connection established
new Admin(connection.db).listDatabases(function(err, result) {
console.log('listDatabases succeeded');
// database list stored in result.databases
var allDatabases = result.databases;
});
});
A very modern approach to get list of all mongo databases using mongoose (version 6.10.*) is to Create a mongoose connection to connect to Mongo's admin database and make sure you have an admin user.
Mongoose object is a very complex object. To list the db's :
const connection = `mongodb://${encodeURIComponent(username)}:${encodeURIComponent(password)}#${hostname}:${port}/admin`
mongoose is a very complex object with promises for executing several functions. to list the db's :
mongoose.connect(connection, { useNewUrlParser: true , useUnifiedTopology: true }).then( (MongooseNode) => {
/* I use the default nativeConnection object since my connection object uses a single hostname and port. Iterate here if you work with multiple hostnames in the connection object */
const nativeConnetion = MongooseNode.connections[0]
//now call the list databases function
new Admin(nativeConnetion.db).listDatabases(function(err, results){
console.log(results) //store results and use
});
})
Result:
{ databases:
[ { name: 'admin', sizeOnDisk: 184320, empty: false },
{ name: 'config', sizeOnDisk: 73728, empty: false },
{ name: 'local', sizeOnDisk: 73728, empty: false },
{ name: 'test', sizeOnDisk: 405504, empty: false } ],
totalSize: 737280,
ok: 1 }
If someone is looking for answers from the latest version of Mongoose and Mongodb, the below code can be used.
import mongoose from 'mongoose';
mongoose.set('strictQuery', true);
mongoose.connect('mongodb://localhost:27017/mydb', {
useNewUrlParser: true,
useUnifiedTopology: true,
});
const db = mongoose.connection;
// Check DB Connection
db.once('open', () => {
(async () => {
const data = await mongoose.connection.db.admin().command({
listDatabases: 1,
});
console.log(data);
})();
console.log('Connected to MongoDB');
});
// Check for DB errors
db.on('error', (err) => {
console.log('DB Connection errors', err);
});
export default mongoose;
If you want to get the database list on your other functions, make sure the connection is established first and also make sure the user has admin access and then just do the below query. This is a sample from my API router.
// Get all databases
router.get('/database/get', async (req, res) => {
try {
const data = await mongoose.connection.db.admin().command({
listDatabases: 1,
});
if (data && data !== null) {
res.status(200).send({ data: data });
return;
}
res.status(200).send({ data: null, message: 'Data not found' });
} catch (e) {
// eslint-disable-next-line no-console
console.log(e);
res.status(500).send(e.message);
}
});
Try running this code. Original take from Gist.