Aggregate.prototype.graphLookup()

Parameters
  • options «Object» to $graphLookup as described in the above link
Returns:
  • «Aggregate»

Appends new custom $graphLookup operator(s) to this aggregate pipeline, performing a recursive search on a collection.

Note that graphLookup can only consume at most 100MB of memory, and does not allow disk use even if { allowDiskUse: true } is specified.

Examples:

  1. // Suppose we have a collection of courses, where a document might look like `{ _id: 0, name: 'Calculus', prerequisite: 'Trigonometry'}` and `{ _id: 0, name: 'Trigonometry', prerequisite: 'Algebra' }`
  2.  aggregate.graphLookup({ from: 'courses', startWith: '$prerequisite', connectFromField: 'prerequisite', connectToField: 'name', as: 'prerequisites', maxDepth: 3 }) // this will recursively search the 'courses' collection up to 3 prerequisites