Next.js tutorial database error

(edited)

https://nextjs.org/learn/dashboard-app/fetching-data

// I add the import ... import { fetchRevenue } from '@/app/lib/data';

// No problem // Add the await fetchRevenue const revenue = await fetchRevenue();

// Error 26 | console.error('Database Error:', error);

27 | throw new Error('Failed to fetch revenue data.');

// Database has all tables and sample data. RLS is disabled. // Googled and found similar errors but not this one. :=( // Thanks for you time and interest.

Vercel Alum

Hi, ! Thanks for your patience 🙏

First, let's check the implementation of the fetchRevenue function. It should be located in the @/app/lib/data.ts file. Can you please confirm that the function looks similar to this?

1export async function fetchRevenue() {2  try {3    // SQL query to fetch revenue data4    const data = await sql<Revenue>`SELECT * FROM revenue`;5    6    return data.rows;7  } catch (error) {8    console.error('Database Error:', error);9    throw new Error('Failed to fetch revenue data.');10  }11}

If this is correct, the error you're seeing suggests that there's an issue with the database connection or the SQL query execution. Here are a few things we can check:

Database Connection: is it correctly set up in your environment variables?
SQL Query: Make sure the 'revenue' table exists in your database and has the correct structure.
Error Handling: Let's modify the error handling to get more information about what's going wrong.

Let me know how you get on!

Screenshot from 2024-12-17 21-20-47 Hello! I have the same problem while going through the tutorial.

I compared two approaches:

Using /postgres (attached a screenshot)
Using postgres (attached a screenshot)

In the first case, that is, when using /postgres, an error 500 is issued (attached a screenshot)

In the second case, that is, when using postgres, data is retrieved from the database without problems (attached a screenshot)

That is, the problem is really on the side of /postgres, and not on the side of the database.

Please help me figure out this problem. I would like to use import { sql } from '/postgres';.

And does /postgres really allow you to protect the site from SQL injections? If so, then I would really, really like you to help with the problem described above.

With respect to you!

reply to #2

Here https://github.com/vercel/next-learn/issues/947 the problem is not resolved

What wrong with sql from /postgres?

With respect

This topic is closed. It no longer accepts new replies.

Hi, ! Thanks for your patience 🙏

First, let's check the implementation of the fetchRevenue function. It should be located in the @/app/lib/data.ts file. Can you please confirm that the function looks similar to this?

1export async function fetchRevenue() {2  try {3    // SQL query to fetch revenue data4    const data = await sql<Revenue>`SELECT * FROM revenue`;5    6    return data.rows;7  } catch (error) {8    console.error('Database Error:', error);9    throw new Error('Failed to fetch revenue data.');10  }11}

If this is correct, the error you're seeing suggests that there's an issue with the database connection or the SQL query execution. Here are a few things we can check:

Database Connection: is it correctly set up in your environment variables?
SQL Query: Make sure the 'revenue' table exists in your database and has the correct structure.
Error Handling: Let's modify the error handling to get more information about what's going wrong.

Let me know how you get on!