We can write: are used to mark up a form with information about what inputs don’t match the schema.In the methods article, we’ll see more about how this works.It’s a fairly straightforward layer on top of the underlying Node Mongo DB driver, but with a synchronous API: It does something totally different!On the client, there is no direct connection to the Mongo DB database, and in fact a synchronous API to it is not possible (nor probably what you want).What this means is that if you have large and complex subfields on document that change often, DDP can send unnecessary changes over the wire.
The key thing to realize is that DDP sends changes to documents at the level of top-level document .
Instead, on the client, a collection is a client side , which pushes data from the server to the client.
Usually, you can assume that the client contains an up-to-date copy of some subset of the full Mongo DB collection. This is a Minimongo collection that has no database connection (ordinarily a collection would either be directly connected to the database on the server, or via a subscription on the client).
They also provide the core of the interactive, connected user experience that users expect from the best applications.
Meteor makes this user experience easy to implement.
Let’s assume that we have a directly, which allows us to check objects against this schema directly whenever we want, such as in a form or Method.