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Simple postgres select query hangs forever when string passed as parameter

I am unable to figure out why the following query fails in node.js with pg PostgreSQL client (version 8.5.1).
db.query("SELECT id FROM my_table WHERE name LIKE $1", ["foo"], (error, results) => {
if (error) {
throw error
}
console.log(results.rows)
});
I do not get a error message and db.query function hangs forever.
However the following works, which I thought would be the same but I am obviously missing something:
db.query("SELECT id FROM my_table WHERE name LIKE 'foo'", ...
My table looks like this and have less then 10 rows:
CREATE TABLE IF NOT EXISTS my_table (
id SERIAL PRIMARY KEY,
name VARCHAR ( 128 ) UNIQUE NOT NULL
);
In case it is relevant, db.query is called from a express app endpoint handler. Also, passing parameters/values to INSERT statements works.
Edit: A prepared statement also works, still do not understand why above do not.
Any suggestions?

Why is Mongoose returning "null" continuing to return null regardless of what I do?

I am able to connect to my MongoDB database and am sure that I am connecting to the correct one. When I try to get a document from the database I always get "null". I am sure that there are documents in the collection as I can see them in Compass.
const theschema = new Schema({
sensor: {
type: String,
required: true
}
})
const model = mongoose.model('Sensor', theschema)
model.findOne({}, function(err, data) {
console.log(data)
})
Above is the code I am currently using for this. I'd appreciate any help possible. Thanks! :)

I think you need to specifie a condition inside curly brackets. In example: Adventure.findOne({ country: 'Croatia' }, function (err, adventure) {}); .
As you can read in docs Note: conditions is optional, and if conditions is null or undefined, mongoose will send an empty findOne command to MongoDB, which will return an arbitrary document. If you're querying by id, use findById() instead.

You can use to find method if you don't have any query to search for (as per your question) and limit it to some value based on each document size and use case (you can limit it to 1 since you are testing connection it seems)
const sensor = mongoose.model('Sensor', theschema)
let query = sensor.find({}).limit(1);
query.exec(function(err, data) {
console.log(data)
})

Just found the problem. The issue was mongoose pluralises collection names therefore it was looking in the wrong collection.
The solution I used was to add this line of code before defining the model
theschema.set('collection', 'Sensor'). This force sets the collection so Mongoose doesn't pluralise it

How to query a bigquery view from bigquery APIs

I have a view in bigquery which contains fields from different datasets and tables, Now I would like to query this view through my google script. What is correct way of doing that.
Actually Currently I have created a separate table in bigquery and querying the table instead of view but I need view as view will get updated when the dependency tables will be updated.
If I am using the table, It is working fine but in case of view I am getting below error:
Exception: Response Code: 404. Message: Not Found.
Bigquery api's to return the result of query.
try {
var job = BigQuery.newJob();
var config = BigQuery.newJobConfiguration();
var queryConfig = BigQuery.newJobConfigurationQuery();
queryConfig.setQuery(sql);
queryConfig.setMaximumBillingTier(5);
config.setQuery(queryConfig);
job.setConfiguration(config);
var jobid = BigQuery.Jobs.insert(job, projectNumber).jobReference;
queryResults = BigQuery.Jobs.getQueryResults(projectNumber, jobid.jobId);
}
catch (err) {
Logger.log(err);
Browser.msgBox(err);
return;
}
// Check on status of the Query Job : MONTHLY
while (queryResults.getJobComplete() == false) {
try {
queryResults = BigQuery.Jobs.getQueryResults(projectNumber, queryResults.jobId);
//queryResults = BigQuery.Jobs.getQueryResults(projectNumber, job.id);
}
catch (err) {
Logger.log(err);
Browser.msgBox(err);
return;
}
}
return queryResults;
If I comment out my first try clause and use below one
try {
var queryRequest = BigQuery.newQueryRequest();
queryRequest.setQuery(sql).setTimeoutMs(100000);
queryResults = BigQuery.Jobs.query(queryRequest, projectNumber);
//Browser.msgBox(queryResults);
}
catch (err) {
Logger.log(err);
Browser.msgBox(err);
return;
}
then It starts giving me
Exception: Query exceeded resource limits for tier 1. Tier 3 or higher required.

It looks like the 'configuration.query.maximumBillingTier' property isn't getting set when you are inserting the job. The method of using 'JobConfigurationQuery' and other classes seems to have been abandoned as there is no mention of them in the current docs, and I needed to resort to using the Wayback Machine to find them.
The most recently available document from 11/12/2013 only defines getters and setters for a few configuration properties, and 'maximumBillingTier' isn't one of them.
I'd suggest manually setting the request properties as is done in the usage examples from the current documentation, rather than relying on the "old" object constructors, as they seem to only be left around for compatibility purposes and are incomplete.
The reason a view would require a higher billing tier versus a table, by the way, is because a view is only a logical table and the queries which define the view must be re-executed when the view itself is queried.

Simple MongoDB query find item age > 10 learnyoumongo find function

I'm going through learnyoumongo and I'm stuck on part 3. Basically a test database is included in the challenge, it is full of parrots, and the goal is to select the parrots whose age is greater than the input. I'm getting a weird error and google is full of mongo 2.x solutions to not exactly the same problem and I'm using mongo 3.0
This is the javascript code:
var mongo = require('mongodb').MongoClient;
var parsedInput = parseInt(process.argv[2]);
var results;
mongo.connect('mongodb://localhost:27017/learnyoumongo', function(err, db){
results = db.collection('parrots').find({ age: { $gt: parsedInput } } ).toArray(function(err, doc) //find if a value exists
{
if(doc) //if it does
{
console.log(doc);
}
else{
console.log(err);
}
});
//console.log(results);
db.close();
});
This is the weird error message:
PS C:\git\learnyoumongo> node .\test.js { [MongoError: server localhost:27017 sockets closed]
name: 'MongoError',
message: 'server localhost:27017 sockets closed' }
I tried restarting mongo, but I'm still not able to pull any of the 'parrots' data out. Even with just find({})

The problem was two pronged - The main issue was I was expecting to be able to run the query with node test.js, and see the results from the parrots collection. But learnyoumongo has atomic tests, meaning they clear the database entirely before and after, so the only way to test was learnyoumongo test.js, and I kept getting an empty result set running the node command.
The other issue was with db.close(), you can't just call db.open and then db.close, because open is async and it would close right after opening, hence the sockets closed error. So you put db.close in the toArray function, or in any other callback of db.open

Node.js and mongodb access mongodb

I'm trying to set up mongodb on Windows 8 using node.js, Does anyone know why im getting this error. C:\users\phill\node_modules\mongodb\lib\mongodb\mongo_client.js:359 it also says at collection = db collection,,, can't call method 'collection' of null. I'm having a hard time setting it up. My goal is to be able to add to mongo db, and see that I add or pull up what I added, but adding something is good enough for me for now. I'm trying every thing I can find, even straight from the website, I tried everything I see on here as well. Think it maybe it's the way I have things set up. My node.js is saved in my c: drive there is a file that says, program files(86x) in there I have node_modules, npm and such. The path ends up being, computer > windows (C:) > program files(86x) > nodejs. My Mongodb is saved right on my C: drive the path end up being windows (C:) > mongodb-win32-x86_64-2008plus-2.4.8. In my C: I also created a file data and in it created another db. I have been told i should just use mongoose, I'm just learning so i open to any advice, links or anything that will help. I have one last question as well, i learned php and then found out about sql injections and stuff like that, i am not seeing anything about security at all, should i expect the same as well. For this i get text not defined, but i have been getting errors with everthing i have done, best i did was get stuck on a right concern screen.
var MongoClient = require('mongodb').MongoClient;
MongoClient.connect("mongodb://localhost:27017/integration_test", function(err, db) {
test.equal(null, err);
test.ok(db != null);
db.collection("replicaset_mongo_client_collection").update({a:1},
{b:1}, {upsert:true}, function(err, result) {
test.equal(null, err);
test.equal(1, result);
db.close();
test.done();
});
});
Tried this as well and getting a error,C:\users\phill\node_modules\mongodb\lib\mongodb\mongo_client.js:359.... at collection = db collection,,, can't call method 'collection' of null. im calling it in command prompt node filename.js I'm saving it where my node.js file is, I have pulled up files before and created a server.
var Db = require('mongodb').Db,
MongoClient = require('mongodb').MongoClient,
Server = require('mongodb').Server,
ReplSetServers = require('mongodb').ReplSetServers,
ObjectID = require('mongodb').ObjectID,
Binary = require('mongodb').Binary,
GridStore = require('mongodb').GridStore,
Grid = require('mongodb').Grid,
Code = require('mongodb').Code,
BSON = require('mongodb').pure().BSON,
assert = require('assert');
var db = new Db('test', new Server('localhost', 27017));
// Fetch a collection to insert document into
db.open(function(err, db) {
var collection = db.collection("simple_document_insert_collection_no_safe");
// Insert a single document
collection.insert({hello:'world_no_safe'});
// Wait for a second before finishing up, to ensure we have written the item to disk
setTimeout(function() {
// Fetch the document
collection.findOne({hello:'world_no_safe'}, function(err, item) {
assert.equal(null, err);
assert.equal('world_no_safe', item.hello);
db.close();
})
}, 100);
});

In your first code example, you said:
For this i get text not defined
I assume you meant "test not defined?" Your script only requires the mongodb library, and I don't believe test is a core nodejs function, so that would explain the error.
To reference the driver documentation for db.collection(), an assert library is used, but also properly imported (as you did in your second example).
Within your callback to db.open(), you don't check if an error occurred. That might shed some light on why db is null in that function.
Regarding your question about the equivalent of SQL injection with MongoDB, the main areas of concern are places where you might pass untrusted input into evaluated JavaScript, or using such input to construct free-form query objects (not simply using a string, but more like dropping an object into your BSON query). Both of these links should provide more information on the subject:
What type of attacks can be used vs MongoDB?
How does MongoDB address SQL or Query injection?