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Learn how to effectively `convert your SQL queries to Laravel's Query Builder`, ensuring smooth transitions and efficient database interactions.
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This video is based on the question https://stackoverflow.com/q/64533768/ asked by the user 'SeyT' ( https://stackoverflow.com/u/13230959/ ) and on the answer https://stackoverflow.com/a/64534444/ provided by the user 'OMR' ( https://stackoverflow.com/u/10573560/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

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How to Convert SQL to Laravel Query Builder: A Step-by-Step Guide

When working with databases, developers often need to translate their SQL queries into a framework like Laravel's Query Builder. This process can sometimes lead to confusion, especially when you encounter discrepancies between raw SQL and the Query Builder syntax. In this guide, we'll address a specific question: How can you convert a raw SQL query that works perfectly into Laravel's Query Builder format?

Understanding the Problem

You may have run into an issue where your SQL query functions correctly but doesn't work in Laravel's Query Builder. For instance, the user had the following SQL:

[[See Video to Reveal this Text or Code Snippet]]

This query retrieves records where the price matches a specific value and a sequence matches the maximum sequence from a related table. However, translating it directly into the Query Builder threw off the user, leading us to explore the correct approach.

Solution Breakdown

To properly convert the SQL statement into Laravel's Query Builder, we need to ensure we follow the correct syntax. Let's break down the necessary steps to achieve this.

Step 1: Structure Your Query

Begin with a basic structure for the Query Builder. In this case, the user initially attempted the following:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Use Parentheses in Raw SQL

One common pitfall is neglecting to include parentheses in your raw SQL expressions. To ensure accurate execution, wrap your subquery in parentheses just like it is formatted in raw SQL.

Step 3: Correct Syntax for Order By

Also, make sure to use the correct casing for your orderBy() method. It should be orderBy instead of OrderBy.

Final Revised Query

Putting it all together, the final Query Builder statement should look like this:

[[See Video to Reveal this Text or Code Snippet]]

Summary of Changes

Parentheses: Ensure subqueries are properly enclosed in parentheses.

Method Naming: Use the correct casing for the orderBy() method.

No Semicolons: Remember that Query Builder commands do not need to end with semicolons.

Conclusion

Translating SQL queries into Laravel's Query Builder can be straightforward if you pay attention to syntax and structure. By following the aforementioned steps, you can efficiently recreate your SQL functionality within Laravel, ensuring your applications run smoothly and effectively.

If you have any more questions about using Laravel's Query Builder or database queries, feel free to ask in the comments below!