mongoose - Delete all referenced objects when deleting referencing object

Question

I have two collections in my app. (Table and Buckets)

Table collection

Bucket collection

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Here each one site has many buckets. I want to delete all buckets and data using site id (site field in table collection)

If it's duplicated, feel free to close this question, but I didn't find the answer after googling, stack overflowing and in the related topics.

Thanks for your help!