Trong Mongoose Model.find () và Model.find (). Execute () cho cùng một kết quả. Vậy tại sao phải sử dụng Model.find (). Execute ()?

Mongoose đã giải thích sự khác biệt của cả hai trong lời hứa ,

Với ví dụ:

const doc = await Band.find({ name: "Guns N' Roses" }); // works

const badId = 'this is not a valid id';
try {
  await Band.find({ _id: badId });
} catch (err) {
  // Without `exec()`, the stack trace does **not** include the
  // calling code. Below is the stack trace:
  //
  // CastError: Cast to ObjectId failed for value "this is not a valid id" at path "_id" for model "band-promises"
  //   at new CastError (/app/node_modules/mongoose/lib/error/cast.js:29:11)
  //   at model.Query.exec (/app/node_modules/mongoose/lib/query.js:4331:21)
  //   at model.Query.Query.then (/app/node_modules/mongoose/lib/query.js:4423:15)
  //   at process._tickCallback (internal/process/next_tick.js:68:7)
  err.stack;
}

try {
  await Band.find({ _id: badId }).exec();
} catch (err) {
  // With `exec()`, the stack trace includes where in your code you
  // called `exec()`. Below is the stack trace:
  //
  // CastError: Cast to ObjectId failed for value "this is not a valid id" at path "_id" for model "band-promises"
  //   at new CastError (/app/node_modules/mongoose/lib/error/cast.js:29:11)
  //   at model.Query.exec (/app/node_modules/mongoose/lib/query.js:4331:21)
  //   at Context.<anonymous> (/app/test/index.test.js:138:42)
  //   at process._tickCallback (internal/process/next_tick.js:68:7)
  err.stack;
}

Ngoài ra: Truy vấn không phải là lời hứa :

const query = Band.find({name: "Guns N' Roses"});
assert.ok(!(query instanceof Promise));

// A query is not a fully-fledged promise, but it does have a `.then()`.
query.then(function (docs) {
  // use docs
});

// `.exec()` gives you a fully-fledged promise
const promise = query.exec();
assert.ok(promise instanceof Promise);

promise.then(function (docs) {
  // use docs
});