How do i manage references?

[apppro123]

Hi i have another question:
How do i manage references?
If i have two schemas and i reference one of the to the other, how to do i insert data to them?
Do i have to insert in both (and give the id of the "second" db to the first) or is it sufficient if i just insert the data into the "main" schema and insert the data of the refrenced element like the schema of the "second" db is built (as an object)?
f.e.
export class CalendarEventModel { name="CalendarEvent" props={Id: "int", Title: "string", Start: "datetime", End: "datetime", Calendar: "#Calendar"};
const CalendarSchema = {name: "Calendar", props: {Id: "int", Title:"string", Color:"string"}};
1.
Calendar.insert({Id: 1, Title:"CalendarExample", Color:"#FFFFFF"});
CalendarEvents.insert({Id: 1, Title: "example", Start: Moment(), End: Moment().add(5, "minutes"), Calendar: 1});
2.
CalendarEvent.insert({Id: 1, Title: "example", Start: Moment(), End: Moment().add(5, "minutes"), Calendar: {Id: 1, Title:"CalendarExample", Color:"#FFFFFF"}});

And which types does datetime take (only date() of js or also Moment.js objects)?

Thank you!

[hieunc229]

Hi @apppro123

1. It will need 2 inserts, for Calendar and CalendarEvents. Besides, Vasern will automatically create an id (lowercase) field.
   (P/s: Custom id has not available yet, you won't need ID in your schema)

   Here is an example, with adding reference object:

   var insertedCalendars = Calendar.insert({ Title:"CalendarExample", Color:"#FFFFFF" });
   
   // Calendar.insert will return an array of objects will be inserted into database with generated id. 
   // For example:
   // insertedCalendars = [
   //     { id: 'a_random_unique_id', Title: "CalendarExample", Color:"#FFFFFF" }
   // ]
   
   var insertedEvents = CalendarEvents.insert({ 
       Title: "example",
       Start: startTime,
       End: endTime,
       Calendar: insertedCalendars[0] // or insertedCalendars[0].id - reference by `id` or actual object
   });

2. Property with datetime will takes either a Date object or a time value in milliseconds. If you use Momentjs, I think you can use .valueOf() to get time in milliseconds. Though, datetime is not timezone aware.

[apppro123]

You have used insertedCalendars[0] in insertedEvents under Calendar: Is it possible to insert objects? Or is it just possible to insert insertedCalendars[0].id?
And is every generated id unique for this element?

[hieunc229]

I'm a bit confuse about the question, pls let me know if my answer isn't what you are looking for.

1. Yes, it's possible to insert an array of reference Calendar objects to CalendarEvents. But the schema needs to be changed to:

   var calendarEventSchema = {
      name: "CalendarEvents",
      props: {
         ...,
         Calendars: "[]#Calendar" // [] means list 
      }
   }

   Then you can pass the array of inserted objects like:

   var insertedEvents = CalendarEvents.insert({ 
       Title: "example",
       Start: startTime,
       End: endTime,
       Calendar: insertedCalendars
   });

2. id generator was inspired with MongoDB ObjectID design, which is highly unique. Though, this element is not uniqued. Currently, to make sure an element is unique, you need to check in the database first (using filter). Sounds like a necessary feature for the upcoming version, I'll take note of this.

Just a head ups, data types will be updated in the next version, so "[]#Calendar" will be deprecated or invalid soon. Also, using lowercase for property name is more preferable.

[apppro123]

Thank you first.
So is it possible to insert an object into an element of the db? I just need one Calendar for one event.

And ty for the tip with lowercase characters.

[hieunc229]

You're welcome. Yes, you can pass either a Calendar object or its id to CalendarEvents as

// it will automatically get and replace the `id` from `insertedCalendars[0]`
Calendar: insertedCalendars[0] 

[apppro123]

Ok thanks!

[hieunc229]

No worries!

[hieunc229]

I will close this issue since it has been resolved. Also, feel free to reopen or create a new one again