1

I have an express server and a simple NeDB database. I can successfully get the whole database like so:

app.get('/api', (request, response) => {
  //queuery the database for everything
  db
    .find({}, (error, data) => {
        if (error) {
          response.end();
          console.log(error)
          return;
        }
      console.log(data)
      response.json(data)
    })

But I noticed the results are, for some reason, not the same order as the database file. I want to sort by one of the timestamps. The database looks like:

...
{"lat":1,"lon":7,"timestamp":1585781054239,"_id":"3cZvJfQyLEXK0SZo","createdAt":{"$$date":1585781054240},"updatedAt":{"$$date":1585781054240}}
{"lat":1,"lon":2,"timestamp":1585781047536,"_id":"DN9bpd1FygEowgtc","createdAt":{"$$date":1585781047538},"updatedAt":{"$$date":1585781047538}}
{"lat":1,"lon":6,"timestamp":1585781052398,"_id":"Dzp6x0xo3QM960Rm","createdAt":{"$$date":1585781052400},"updatedAt":{"$$date":1585781052400}}
{"lat":1,"lon":5,"timestamp":1585781051174,"_id":"KswtMYzV2QBE3xkb","createdAt":{"$$date":1585781051176},"updatedAt":{"$$date":1585781051176}}
...

I admittedly haven't quite wrapped my head around how the callbacks work in this code. I have tried something like the following but it returns a 500 GET error to the client and returns "TypeError: Cannot read property 'sort' of undefined" to the server:

app.get('/api', (request, response) => {
  //queuery the database for everything
  db
    .find({}, (error, data) => {
        if (error) {
          response.end();
          console.log(error)
          return;
        }
      // console.log(data)
      // response.json(data)
    })
    .sort({ createdAt: -1 }, (data) => {
    console.log(data)
    response.json(data)
  });
});

I wonder if it should be nested in the .find() function but at this point I'm quite in over my head and I believe I'm just not understanding the syntax. I have found examples of sorting but not in this context.

nonethewiser
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1 Answers1

0

You can write something like this to sort it via timestamp:

database.find({}).sort({"timestamp":-1}).exec(function(err, data) {
    if (err) {
        response.end();
        return;
    }
    console.log(data);
});
Tyler2P
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Pranav
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