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Created February 19, 2020 12:04
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Data Modelling cheatsheet
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cheatsheet_data_modelling.md

Data Modelling Cheatsheet

Identifying relations

A relation between two tables A and B where a foreign key of A is (part of) the primary key of B.

CREATE TABLE AuthoredBook (
  author_id INT NOT NULL,
  book_id INT NOT NULL,
  PRIMARY KEY (author_id, book_id),
  FOREIGN KEY (author_id) REFERENCES Authors(author_id),
  FOREIGN KEY (book_id) REFERENCES Books(book_id)
);

The relations Authors:AuthoredBook and Books:AuthoredBooks are identifying.

https://stackoverflow.com/questions/2814469/still-confused-about-identifying-vs-non-identifying-relationships/2814663#2814663

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