iOS

Pitfall: Parse Circular Dependency Error and Bidirectional Relationship

When you save a PFObject and encounter the error Found a circular dependency when saving, it could be due to you setting a bidirectional/inverse relationship.

Take this example:

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// You have 2 Parse Class Teacher and Student
PFObject *teacher, student;
// You try to set up the bidirectional relationship
teacher.student = student
student.teacher = teacher

Upon save, the code will throw the exception Found a circular dependency when saving. This is because bidirectional relationship is not supported on Parse.

The solution requires 3 steps:

  • Don’t set up any of the relationship, and save teacher first. Saving will provide teacher.objectId.
  • Then save student with 1 directional relationship to teacher. Saving will provide student.objectId.
  • Then update teacher with the relation to student.

This takes 3 API requests to set up.

Not good, but workaround the limitation of Parse.

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