One to Many Relationships: Overview

• What is a "one to many" relationship?

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  • One item maps directly to many related items

• When would you use a "one to many" relationship?

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  • Example: Customer --> Purchases

• How can you build "one to many" relationships in MongoDB?

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  • "Normalized" approach: multiple collections linked with common keys
  • Using an array of embedded documents
  • Using an array of DBRef documents