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SQL에서 데이터 조인하기

Maham Faisal Khan

Senior Content Developer, DataCamp

일대다 관계

A diagram showing three books (Persuasion, Pride and Prejudice, and Emma) connected to one author, Jane Austen.

일대다 관계

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A diagram showing that one fingerprint can only be associated with one traveler.

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다대다 관계

A diagram showing that many languages can be associated with many countries, and many countries can be associated with one language. Belgium has three official languages: French, German, and Dutch. Conversely, languages can be official in many countries: Dutch is an official language of both the Netherlands and Belgium, but not Germany.

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SQL에서 데이터 조인하기