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Generating and Downloading CSV files using express JS

David Okonji on May 18, 2020

While working on a node JS project, I had the need to pull certain data from my database and represent values in a CSV file, This guide aims at sim...
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Alex Solonenko

Actually, I'm not a Front End dev, and my knowledge of js and node is quite a little, but I can help you to improve your solution.
Postgres has a very nice feature called "COPY FROM". It can copy any data from your database in the CSV format with the header as well.
So basically you don't need to have a json_to_converter and any orm at all.
Just using the "COPY TO STDOUT" and js streams you are able to build a very powerful and nice solution, which will help you to get any data from the database no matter how it will be large in size. you will be limited only with your bandwidth.

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David Okonji

Thank you, Alex, Yeah sure an ORM is not necessary, I would surely try out the alternate solution suggested.

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Pacharapol Withayasakpunt • Edited

You should also streaming, especially if CSV is large.

Maybe by piping CSV stream.

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Joel Ndoh

Hello, I love the article. But I do have some questions.

In a situation where I gotten the data I need from mongodb and I applied .populate

However, I would like to get access to a certain field in the populated field. How do I do that.

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David Okonji

Hello Joel, hope I’m not too late, if you use populate then you would have a nested object, the library supports dots notation, for example, you have a user object with Id key, it would be value: 'user.id'

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Ese

This was very helpful David, Thanks. Just wondering how it will be handled in the frontend.

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David Okonji

From the frontend, it can be sent as Formdata payload

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Ese

Thank you!

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This Dot Media

This is awesome! Thanks David 😁

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Akanbi Lawal Tunde

Nice read!!

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Donald Ng

Thank you this is really helpful!

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Cavdy

This is beautiful... thanks

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Kumar

Much needed one for me. Thanks :)

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Luan Mota Coleto

Thanks, it was really helpful

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eliyahuKriel

thanks!! very helpfull
how can i set the file to be support hebrew lang? when download the file its look like
%$#@$R@F

thanks

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David Okonji

Hello, I am not quite sure, it depends on how the data is stored in the database.