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A comment on Comparison of Joins: MongoDB vs. PostgreSQL. Parent comment

Re:Comparison of Joins: MongoDB vs. PostgreSQL by alexpetralia on Friday April 10, 2020 @01:08PM (#22834991)
I don't think most document stores enforce foreign key relationships (and hence consistency) like RDBMS do, so in practice that would make joins difficult.
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Re:Comparison of Joins: MongoDB vs. PostgreSQL by d_watt on Friday April 10, 2020 @01:53PM (#22835472)
Is joining on an fkey any more performant than without it assuming the same indexing is applied?

When you say difficult do you mean from a developer ergonomics standpoint (knowing there's data integrity), or from a database optimizability standpoint?

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Re:Comparison of Joins: MongoDB vs. PostgreSQL by alexpetralia on Friday April 10, 2020 @03:18PM (#22836409)
The former. You have a guarantee of consistency, whereas otherwise you must adjust for this in your application code. Database performance wise I agree they are equivalent.
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