MongoDB, using Mongoose duplicate key error index?

Question

I have a MEN (MongoDB, Express, Node) application, and when i'm inserting the first item everything is fine, but when i want to add a second one I get this error:

E11000 duplicate key error index: local.movies.$title_1 dup key: { : null }

If I then delete the first row, and then insert one item again it works, but again when I want to add a second item I keep getting the error.

I am really pulling my hair on this one, and can't seem to find the problem :(

Hopefully someone can help me :)

Btw how can I access my table from command line? I tried db.movies.find(), movies.find() and other options, but nothing happens, and when i type show collestions I only get system.indexes. And how can i delete the table from command line and try to make a new one?

This is my model:

var mongoose = require('mongoose');
var MovieSchema = require('../schemas/movie');
var Movies = mongoose.model('Movie', MovieSchema);
module.exports = Movies;

This is my schema:

var mongoose = require('mongoose');
var MovieSchema = new mongoose.Schema(
        {
            movieTitle: { type: String, required: true, index: { unique: true } },
            movieYear: { type: String, required: true },
            movieDirector: { type: String, required: true },
            movieImdbLink: { type: String, required: true }
        }
    );
    module.exports = MovieSchema;

I've also tried without index, movieTitle: { type: String, required: true }

This is my insert/update function:

// insert/update movie
exports.save = function(req, res){
    var _id = (req.body._id !== 'undefined') ? req.body._id : null;
    var movieTitle = req.body.movieTitle;
    var movieYear = req.body.movieYear;
    var movieDirector = req.body.movieDirector;
    var movieImdbLink = req.body.movieImdbLink;
    var movie = null;
    if(_id){
        var query = {_id: _id};
        Movies.update(
            query,
            {
                $set:{
                    movieTitle: movieTitle,
                    movieYear: movieYear,
                    movieDirector: movieDirector,
                    movieImdbLink: movieImdbLink
                }
            },
            {safe:true},
            function(err, result, raw){
                if(err){
                    console.log(err);
                    res.send(500);
                }
                else{
                    res.send(200);
                }
            }
        );
    }
    else{
        movie = new Movie(
            {
                movieTitle: movieTitle,
                movieYear: movieYear,
                movieDirector: movieDirector,
                movieImdbLink: movieImdbLink
            }
        );
        movie.save(function(err){
            if(err){
                res.redirect('/movies/?msg=' + err.message);
            }
            else{
                res.redirect('/movies');
            }
        });
    }
};

Answer 1

movieTitle has an index with unique:true. This index is created when the app is started for the first time. The rest of the times, mongoose checks to see if the index exists. If it doesn't it will create it.

When you remove the unique declaration, mongoose doesn't recreate the index as you would excpect. Maybe in feature versions it will.

You have to manually drop the index (see mongo docs), or the whole db.

After restarting your app the new index will be created.

I hope that helps

Answer 2

Mongoose doesn't recreate index

So, if you had created a index with unique equal to true it cant be changed until either index is dropped or db is dropped.

So simply drop either your database or tittle index and recreate it with unique=false