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Difference between .exec() and .execPopulate() in Mongoose?

Here I answer what is the difference between .exec() and .execPopulate() in Mongoose?

  1. .exec() is used with a query while .execPopulate() is used with a document
Syntax for .exec() is as follows:
Model.query()
  .populate('field')
  .exec() // returns promise
  .then(function (document) {
    console.log(document);
  });
Syntax for .execPopulate() is as follows:
fetchedDocument
  .populate('field')
  .execPopulate() // returns promise
  .then(function (document) {
    console.log(document);
  });
When working with individual document use .execPopulate(), for model query use .exec(). Both returns a promise. One can do without .exec() or .execPopulate() but then has to pass a callback in populate.

Comments

  1. Admin10 March 2020 at 06:30

    thanks, understood the difference in first line itself.
    "exec() is used with a query while .execPopulate() is used with a document"

    ReplyDelete

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