Database quiz thread

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@ivan, the final quiz question might be not consistent enough. See the explanation of my opinion below :

Not sure why “NO SQL” database is not applicable to the mission critical finance app. I guess, it is supposed to have a “consistent” trait mentioned in the CAP theorem.
Maybe it should have “availability” trait given my understanding of “mission critical” is correct. It does not really matter if the database engine has SQL as a query language or not.

Here are some good examples :

  • dBase
  • Clipper
  • Fox Pro

All of them were used in financial applications and they do not have SQL (since it has not been invented or popularized yet back then)

The statement NO SQL == MongoDB is incorrect since it is not transitive. Meaning mongo is a NO SQL database but Not any NO SQL database is Mongo DB.

P.S. Here is a good book on databases to mention if you have not done so yet


All good until now thanks for the course is really helpfull

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Thanks for these added details.
After that, I do think the 3rd quiz question should have been better precised: for instance, atomic updates needed or not? with excluding answers

Very helpful - thank you all.
Technology has come along way since I was in College, very enlightening, this digital world.

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As per my understanding, an SQL database is also known as ‘Relational Database’ where data is structured. It also focuses on a relational model, and therefore I believe that the correct answer to the question is ‘Whenever you know that the data has a strict structure and relationships’, instead of the first one, i.e., ‘whenever you know that the data is semi-structured’.

Could someone please advise on this and correct me if I’m wrong? Thank you in advance.

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Can someone give me more explanation on this. From my understanding SQL is all about well structured and Relational data, why then is the answer wrong?

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Hey @JoJo, @rishibehl4, hope you guys are well.

Not all the times you know the structure of the data, all you know if that the data might need some structure or relationships between them, so the correct answer is “whenever you know that the data is semi-structured”. Because not always you will know that information from the data, so SQL is just applied to data that needs an structure or relations, when you know there must be some kind of structure between them (semi-strucutre).

Hope it helps.

Carlos Z

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Thank you @thecil for the clarification.