Outputting id Only with .find()

[CodeManFantastic]

Hi all,

I am having a problem when trying to show my other columns in my .find() statement its only outputting the following, how do I make it show my other columns too that are shown in the query.

Console -

Express is running on port 3000
Mongoose connection open on mongodb://localhost:27017/test
School { _id: 5aa93d03f7f57e04503b4695 }

Model -

const mongoose = require('mongoose');

const schoolsSchema = new mongoose.Schema({
  Boarders: {
    type: String,
  },
  Gender: {
    type: String,
  },
   Town: {
    type: String,
  },
});

module.exports = mongoose.model('School', schoolsSchema);
mongoose.Promise = global.Promise;

App.js

app.get('/console', (req, res, next) => {
    School.find({"Boarders": {'$regex': 'No B'}, "Gender": {'$regex': 'Mixed'}, "Town": {'$regex': 'London'}}, {"_id": 0, "Boarders": 1, "Gender": 1, "Town": 1})
        .exec(function (err, items) {
            if (err) { return next(err); }
            var myData = new School(req.body)
            console.log('School', myData);
            res.send('Check console.log for list of items');
        });
});

Html app -

      <h1>Select names to database<h1> 
    <form method="GET" action="/console">
<label>Select gender town <label> 
  
    <input type="submit" value="Select">
    </form>

[m_hutley]

@CodeManFantastic

var myData = new School(req.body)

Isn’t… the purpose of the ‘items’ variable in the exec function to already do this?

If you’re expecting a single response, then findOne would be more appropriate…
If you’re expecting multiple responses,then a loop over items would be more appropriate.

What happens if you instead do:

.exec(function (err, items) {
            if (err) { return next(err); }
            items.forEach(function (item) {
                      console.log('%s: %s %s', item.Town, item.Gender, item.Boarders);
            });
            res.send('Check console.log for list of items');
        });

?

[CodeManFantastic]

I used the following - nothing happened other than it showed check console.log for list of items

app.get('/console', (req, res, next) => {
    School.find({"Boarders": {'$regex': /No B/}, "Gender": {'$regex': 'Mixed'}, "Town": {'$regex': 'London'}}, {"_id": 0, "Boarders": 1, "Gender": 1, "Town": 1})
        .exec(function (err, items) {
            if (err) { return next(err); }
            items.forEach(function (items) {
                      console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);
            });
            res.send('Check console.log for list of items');
        });
});

I then tried the following for testing and it shows underfined: undefined undefined

app.get('/console', (req, res, next) => {
    School.find({"Boarders": {'$regex': /No B/}, "Gender": {'$regex': 'Mixed'}, "Town": {'$regex': 'London'}}, {"_id": 0, "Boarders": 1, "Gender": 1, "Town": 1})
        .exec(function (err, items) {
            if (err) { return next(err); }
            items.forEach(function (items) {
                      console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);
            });
            res.send('Check console.log for list of items');
            console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);
        });
});

[Dormilich]

what does console.log(items) show?

[CodeManFantastic]

I currently get the following

I changed the code to

app.get('/console', (req, res, next) => {
    School.find({"Boarders": {'$regex': /No B/}, "Gender": {'$regex': /Mixed/}, "Town": {'$regex': /London/}})
        .exec(function (err, items) {
            if (err) { return next(err); }
            items.forEach(function (items) {
                      console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);
            });
            res.send('Check console.log for list of items');
            console.log(items)
        });
});

Now I get the following

Express is running on port 3000
Mongoose connection open on mongodb://localhost:27017/test
[]

[m_hutley]

So… obvious question… does the document collection you’ve connected to actually contain a record that matches your search?

[CodeManFantastic]

Yes it does its meant to show the following; I tested this with Studio3T

{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }

[m_hutley]

So what happens if you do a simpler query:

 School.find({"Town": 'London'})

EDIT: Or for that matter, pull ALL the records.

School.find({})

[CodeManFantastic]

Shows exact same result

[m_hutley]

Then… are you absolutely sure you’ve connected to the correct datastore and collection? If you run the empty object query, it should dump back every document in the collection…

[CodeManFantastic]

ok I have started to do it another way

var url = "mongodb://localhost:27017/";

app.get('/console', (req, res, next) => {
mongoose.connect(url, function(err, db) {
  if (err) throw err;
  var dbo = db.db("CSV");
  dbo.collection("Schools").find({"Boarders": {'$regex': /No B/}, "Gender": {'$regex': /Mixed/}, "Town": {'$regex': /London/}}).toArray(function(err, result) {
    if (err) throw err;
    console.log(result);
    db.close();
  });
});
});

its looking more promosing but errors currently include

(node:12108) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): TypeError: db.db is not a function
(node:12108) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

[m_hutley]

@CodeManFantastic

TypeError: db.db is not a function

Well, that seems like a rather obvious error…
console.log(db)

[CodeManFantastic]

instead of console.log(result); ?

[m_hutley]

The error messages you’re getting sound like the connection to your database failed.

[CodeManFantastic]

I have routed back to the previous code as the W3Schools tutorial did not help

app.get('/console', (req, res, next) => {
    Schools.find({Boarders: {'$regex': /No B/}, Gender: {'$regex': 'Mixed'}, Town: {'$regex': 'London'}}, {_id: 0, Boarders: 1, Gender: 1, Town: 1})
        .exec(function (err, items) {
            if (err) { return next(err); }
            items.forEach(function (items) {
                   console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);  
            });
            res.send('Check console.log for list of items'); 
            console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);
        });
});

When I click the button in html it now shows

Express is running on port 3000
Mongoose connection open on mongodb://localhost:27017/test
Mongoose connection open on mongodb://localhost:27017/CSV
undefined: undefined undefined

So it is going into the CSV database as its CSV.Schools although it is coming up as undefined

[m_hutley]

Just… for SAG, lets try this…

app.get('/console', (req, res, next) => {
    var entry = new Schools({'Town':'London','Gender':'Mixed','Boarders':'No B'})
    entry.save(function (err) { console.log("Couldn't write.") });

    Schools.find({Boarders: {'$regex': /No B/}, Gender: {'$regex': 'Mixed'}, Town: {'$regex': 'London'}}, {_id: 0, Boarders: 1, Gender: 1, Town: 1})
        .exec(function (err, items) {
            if (err) { return next(err); }
            items.forEach(function (items) {
                   console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);  
            });
            res.send('Check console.log for list of items'); 
            console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);
        });
});

[CodeManFantastic]

hmm very interesting
so it spits out the following

Express is running on port 3000
Mongoose connection open on mongodb://localhost:27017/test
Mongoose connection open on mongodb://localhost:27017/CSV
No B: Mixed London
/No B/: /Mixed/ /London/
undefined: undefined undefined
Couldn't write.

I changed the code a little too

app.get('/console', (req, res, next) => {
    var entry = new Schools({"Town":/London/,"Gender":/Mixed/,"Boarders":/No B/})
    entry.save(function (err) { console.log("Couldn't write.") });

    Schools.find({Boarders: {'$regex': /No B/}, Gender: {'$regex': 'Mixed'}, Town: {'$regex': 'London'}}, {_id: 0, Boarders: 1, Gender: 1, Town: 1})
        .exec(function (err, items) {
            if (err) { return next(err); }
            items.forEach(function (items) {
                   console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);  
            });
            res.send('Check console.log for list of items'); 
            console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);
        });
});

[m_hutley]

Well i’ve flubbed the code slightly.

app.get('/console', (req, res, next) => {
    var entry = new Schools({"Town":/London/,"Gender":/Mixed/,"Boarders":/No B/})
    entry.save(function (err) { if (err) { raise err; });

    Schools.find({Boarders: {'$regex': /No B/}, Gender: {'$regex': 'Mixed'}, Town: {'$regex': 'London'}}, {_id: 0, Boarders: 1, Gender: 1, Town: 1})
        .exec(function (err, items) {
            if (err) { return next(err); }
            items.forEach(function (items) {
                   console.log('%s: %s %s', items.Boarders, items.Gender, items.Town);  
            });
            res.send('Check console.log for list of items'); 
        });
});

The response you got seems to indicate the collection you’re connecting to is empty, because it managed to successfully return the object that I wrote into the collection just there…

[CodeManFantastic]

Ok great yep I have tested it and it comes up with

Express is running on port 3000
Mongoose connection open on mongodb://localhost:27017/test
Mongoose connection open on mongodb://localhost:27017/CSV
No B: Mixed London
/No B/: /Mixed/ /London/
/No B/: /Mixed/ /London/
/No B/: /Mixed/ /London/
/No B/: /Mixed/ /London/
/No B/: /Mixed/ /London/
/No B/: /Mixed/ /London/
/No B/: /Mixed/ /London/

I need to try and output the following, I know my model works because we have just tested it so do you believe its the connection to the collection that is causing this or could it be the statement I am using

I just copied this from Studio3T into here so I know it works but I need to try and connect it somehow

db.Schools.find({"Boarders": {'$regex': 'No B'}, "Gender": {'$regex': 'Mixed'}, "Town": {'$regex': 'London'}}, {"_id": 0, "Boarders": 1, "Gender": 1, "Town": 1});

The results -

{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }
{ "Town" : "London", "Boarders" : "No Boarders", "Gender" : "Mixed" }

[m_hutley]

Which database is Studio3T connected to? You’ve defined two - test and CSV. You’ve defined a collection within it, “Schools”, though originally your model pointed to a collection named School rather than Schools…