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5 mistakes to avoid when getting started with GraphQL

Tomek Poniatowicz on March 15, 2019

Being short-sighted It’s a mistake that can lead to serious complications later on. Thinking about your schema try being as predictive a...
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Petar G. Petrov • Edited

Nice write up! I don't have any GraphQL experience, but I'm trying to get into it. I've got one question about the paragraph:

This is very negligent as GraphQL it's all about reducing the number of database calls. The GraphQL preferable way is nesting the output types which makes it easier to call your database with a single request and batch your data:

As far as I understand it, DataLoader's batching works on the event-loop level. When it comes to SQL databases it'd still be the responsibility of the backend that fetches the data from the database to actually provide the right (optimized) query, right? I mean, a batch could still result in several SQL SELECTs, if a query with a, e.g., WHERE clause, isn't available.

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Artur Czemiel

In my opinion dataLoader is more abstract tool which can be used within specific patterns. It doesn't replace SQL queries of course, but you might be confused by a lot of SQL examples inside README. Using it with resolvers and GraphLQ is up to you. You can reduce the number of calls if you want to query just exact fields.

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Hassan Farid

+1 - I have same question. API returns the results all at once, but database get queried in each loop, instead of joins that are possible in most SQL data sources.

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Truong Hoang Dung • Edited

For graphql, what i need is automatic fragments, typings, queries, mutations generation. Those are selling points of graphql, so if you have to manually type graphql query, you're doing it non-optimally.

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Gerardo Lima

Yes, yes drop REST at all... What a fraud. Would you implement a single SP to fetch all data from a database? Why the hell one would think doing that with http requests world work nicely?

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Tomek Poniatowicz

Calm down :) What I meant is that you should stop being blindfolded and open your eyes on GraphQL.

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Gerardo Lima

You are right, @Tomek :) I've just read too many hype articles praising GraphQL as a silver bullet and I took it all on yours ... my bad.

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Ian Rathbone

Thanks very useful!

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Łukasz Żarski

Thanks, that was useful!