How to declare collection name and model name in mongoose

Question

I have 3 kind of records,

1)Categories,
2)Topics  and
3)Articles 

In my mongodb, i have only 1 colection named 'categories' in which i stroe the above 3 types of documents.

For these 3 modules,i wrote 3 models(one each) in such a way like below,

mongoose.model('categories', CategorySchema);
mongoose.model('categories', TopicSchema)
mongoose.model('categories', ArticlesSchema)

like....mongoose.model('collection_name', Schema_name)

but when i run my code ,it throws error that

Cannot overwrite `categories` model once compiled.

If i change the above models like this,

mongoose.model('category','categories', CategorySchema);
mongoose.model('topics','categories', TopicSchema)
mongoose.model('articles','categories', ArticlesSchema)

It is creating 2 collections named topics and articles which i dont want. This is my issue right now,can anyone suggest me help.....Thanks....

Answer 1

Try-

mongoose.model('category', CategorySchema, 'categories');
mongoose.model('topics', TopicSchema, 'categories');
mongoose.model('articles', ArticlesSchema, 'categories');

As mentioned in docs: http://mongoosejs.com/docs/api.html#index_Mongoose-model

Mongoose#model(name, [schema], [collection], [skipInit])

Defines a model or retrieves it.

Parameters:

• 1st param - name <String> model name
• 2nd param - [schema] <Schema> schema name
• 3rd param - [collection] <String> collection name (optional, induced from model name)
• 4th param - [skipInit] <Boolean> whether to skip initialization (defaults to false)

See - https://stackoverflow.com/a/14454102/3896066

Answer 2

As you stated, When you write this,

mongoose.model('categories', CategorySchema);
mongoose.model('categories', TopicSchema);
mongoose.model('categories', ArticlesSchema);

The output becomes inappropriate so do this instead,

mongoose.model('category', CategorySchema);
mongoose.model('topic', TopicSchema);
mongoose.model('article', ArticlesSchema);

Bonus tip. Mongoose makes your collection name plural by default so change a little code if you want your collection name as you wrote.

mongoose.model('category', CategorySchema,'category');
mongoose.model('topic', TopicSchema,'topic');
mongoose.model('article', ArticlesSchema,'article');