<!DOCTYPE html>
<html>
 <head>
  <title>
   Refinedev - Hasura: Mastering Nested/Multiple Query Roots
  </title>
  <style>
   body {
      font-family: sans-serif;
    }
    h1, h2, h3 {
      margin-top: 30px;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
      margin: 20px auto;
    }
    code {
      background-color: #f0f0f0;
      padding: 5px;
      font-family: monospace;
    }
  </style>
 </head>
 <body>
  <h1>
   Refinedev - Hasura: Mastering Nested/Multiple Query Roots
  </h1>
  <p>
   This article delves into the powerful concept of nested and multiple query roots within the Refinedev and Hasura ecosystem. We'll explore how these techniques empower you to structure complex data queries and build highly dynamic user interfaces with ease.
  </p>
  <h2>
   Introduction: Query Roots and Their Significance
  </h2>
  <p>
   In the realm of data fetching and UI rendering, understanding query roots is fundamental. A query root represents the entry point for your data requests. In the context of Refinedev and Hasura, a query root is typically a GraphQL query that fetches the initial data structure for your application's UI. The beauty of Refinedev lies in its seamless integration with Hasura, enabling you to define and utilize these query roots efficiently.
  </p>
  <p>
   Nested and multiple query roots introduce flexibility and granularity to your data fetching strategies. Let's break down why this matters:
  </p>
  <ul>
   <li>
    <strong>
     Improved Data Management:
    </strong>
    By defining separate query roots for different sections of your application, you can organize your data fetching logic in a structured manner. This makes it easier to maintain and understand your codebase.
   </li>
   <li>
    <strong>
     Reduced Data Overfetching:
    </strong>
    Instead of fetching an entire data set at once, you can selectively retrieve only the data needed for a particular UI component or section. This optimizes performance and minimizes unnecessary network requests.
   </li>
   <li>
    <strong>
     Enhanced User Experience:
    </strong>
    Nested query roots allow for progressive data loading, providing a smoother user experience. As users navigate your application, additional data can be fetched as needed, leading to a more responsive and engaging interaction.
   </li>
  </ul>
  <h2>
   Deep Dive: Concepts and Techniques
  </h2>
  <p>
   Let's explore the key concepts and techniques associated with nested and multiple query roots:
  </p>
  <h3>
   1. Refinedev's Query Root Structure
  </h3>
  <p>
   Refinedev provides a powerful component called
   <code>
    <refine>
    </refine>
   </code>
   that serves as the central hub for your application's data fetching and UI management. It's here that you define your query roots:
  </p>
  <pre><code>
import { Refine } from '@pankod/refine';
import { HasuraProvider } from '@pankod/refine-hasura';

function App() {
  return (
    <refine 'https:="" 'your-admin-secret',="" adminsecret:="" dataprovider="{HasuraProvider({" url:="" your-hasura-endpoint',="" })}="">
      {/* ... Your application components here */}
    </refine>
  );
}
</code></pre>
  <h3>
   2. Nested Query Roots: Structure and Implementation
  </h3>
  <p>
   Nested query roots allow you to create a hierarchical structure for your data requests. This is particularly useful when you need to fetch related data that is dependent on a primary resource.
  </p>
  <h4>
   Example: Fetching Products and Their Categories
  </h4>
  <p>
   Consider a scenario where you have a product list page that displays products along with their respective categories. You can define a nested query root like this:
  </p>
  <pre><code>
// Example for Products and Categories
const ProductRoot = ({ id }) =&gt; (
  <query enabled="{!!id}" root="Product">
    <query 'description',="" 'name',="" ]}="" _eq:="" add="" any="" category="" data.product.category_id="" fields="" id:="" need="" other="" root="Category" where="{{" you="" {="" }="" }}=""></query>
  </query>
);
</code></pre>
  <img alt="Nested Query Root Example" src="https://i.imgur.com/lF1q35O.png"/>
  <p>
   In this example, the nested
   <code>
    Category
   </code>
   query root is used to fetch the category information based on the
   <code>
    category_id
   </code>
   associated with the currently selected product.
  </p>
  <h3>
   3. Multiple Query Roots: Independent Data Requests
  </h3>
  <p>
   Multiple query roots enable you to fetch data independently from different sources, allowing you to construct complex UI layouts with data from multiple endpoints.
  </p>
  <h4>
   Example:  Displaying Products and User Information
  </h4>
  <p>
   Imagine a dashboard where you need to display a list of products and the current user's profile details.
  </p>
  <pre><code>
// Example for Products and User Details
const UserRoot = () =&gt; (
  <query 'email',="" 'name',="" ]}="" add="" any="" fields="" need="" other="" root="User" user="" you=""></query>
);

const ProductRoot = () =&gt; (
  <query 'name',="" 'price',="" ]}="" add="" any="" fields="" need="" other="" product="" root="Product" you=""></query>
);
</code></pre>
  <img alt="Multiple Query Root Example" src="https://i.imgur.com/m5j6Y3a.png"/>
  <p>
   In this scenario,
   <code>
    ProductRoot
   </code>
   fetches data for products, while
   <code>
    UserRoot
   </code>
   fetches data for the current user. These requests are independent and can be handled concurrently, leading to faster page loading times.
  </p>
  <h2>
   Step-by-Step Guide: Implementing Nested and Multiple Query Roots
  </h2>
  <p>
   Let's walk through a practical implementation of nested and multiple query roots within a Refinedev application powered by Hasura. For this guide, we'll use a simple example of a blog application.
  </p>
  **1. Project Setup:**

- Install Refinedev and the Hasura provider:

bash
npm install @pankod/refine @pankod/refine-hasura


- Create a basic Refinedev application structure:

bash
src/
├── App.js
└── components/
└── BlogPost.js


**2. Define Your Hasura GraphQL API:**
  <p>
   Ensure you have a Hasura instance running with a database schema for your blog data (e.g., a
   <code>
    Post
   </code>
   table and an associated
   <code>
    Author
   </code>
   table).
  </p>
  **3. Implement Nested Query Roots for Blog Posts and Authors:**

javascript
// components/BlogPost.js
import React from 'react';
import { Query, useData } from '@pankod/refine';

const BlogPost = ({ id }) => {
const { data } = useData({
resource: 'Post',
query: ({ query }) => ({
query: {
select: {
title: true,
content: true,
author: {
select: {
name: true,
},
},
},
},
}),
id,
});

if (!data) {
return

Loading...

;
}

return (

{data.title}

By {data.author.name}

{data.content}

);
};

export default BlogPost;


**4. Implementing Multiple Query Roots for Posts and User Details:**

javascript
// src/App.js
import React from 'react';
import { Refine, Query } from '@pankod/refine';
import { HasuraProvider } from '@pankod/refine-hasura';
import BlogPost from './components/BlogPost';

const UserRoot = () => (

);

const BlogPostRoot = () => (

);

function App() {
return (

{/* ... Other application components */}

);
}

export default App;


**5. Integrate the Nested Query Root in Your UI:**

// ... (rest of the code from above)

function App() {
return (

{/* ... /}

{/ Example: Displaying a specific post with id 1 */}

);
}

  <h2>
   Conclusion: Leveraging Query Roots for Enhanced Data Fetching
  </h2>
  <p>
   Nested and multiple query roots are invaluable tools for building complex and performant applications using Refinedev and Hasura. By mastering these techniques, you can:
  </p>
  <ul>
   <li>
    <strong>
     Structure your data fetching logic effectively
    </strong>
    , making your codebase more manageable.
   </li>
   <li>
    <strong>
     Optimize performance
    </strong>
    by reducing unnecessary data overfetching.
   </li>
   <li>
    <strong>
     Enhance the user experience
    </strong>
    with progressive loading and smooth navigation.
   </li>
  </ul>
  <p>
   As you embark on your Refinedev and Hasura journey, remember that well-defined query roots are the foundation of efficient data management. Embrace nested and multiple query roots to unlock the full potential of this powerful combination. Happy coding!
  </p>
 </body>
</html>

Notes:

This example is a basic implementation and can be extended to handle more complex scenarios.
You need to replace "https://your-hasura-endpoint" and "your-admin-secret" with your actual Hasura endpoint URL and admin secret.
This code uses the @pankod/refine-hasura package, which is a Refinedev provider for connecting to Hasura.
The useData hook provided by Refinedev allows you to access data fetched using the Query component.
The Query component is used to define the GraphQL queries for fetching data from Hasura.
This article provides a solid foundation for understanding nested and multiple query roots in Refinedev and Hasura. You can further explore advanced concepts like pagination, filtering, sorting, and other data management features in Refinedev's documentation.

refinedev - hasura (nested/multiple query_root)

{data.title}