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Learn how to efficiently retrieve Laravel Eloquent deals that include null fields and enforce relationship conditions with simple queries.
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Retrieving Laravel Eloquent Records with Null Fields in Relationships

Laravel is a powerful framework that makes it easy to work with databases through Eloquent, its built-in Object-Relational Mapping (ORM) system. However, developers often encounter challenges when trying to retrieve records that include relationships while ensuring specific fields are null.

In this guide, we'll explore a common problem faced by Laravel developers: how to retrieve records which have empty fields in the main model and also ensure that specific related model fields (like email) are considered null.

The Problem

Imagine you have a Deal model that tracks various information, including user details and transaction information. In your application, you might need to return a list of deals that meet two criteria:

Some fields in the Deal model are null.

The related Person model also has a null email field.

This scenario becomes tricky when you realize that conventional querying methods may not retrieve both criteria effectively. You may notice that even if some Deal records meet the first condition, their related Person records might not satisfy the second condition, leading to incomplete results.

Example Scenario

Given below is a sample model and query setup:

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

When querying your Deal records like this:

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

You would retrieve deals where certain fields are empty, but what about deals where the associated person lacks an email?

The Solution

To effectively address this issue, we can utilize a join statement, allowing us to combine the relevant records from both the deals and the people tables.

Implementing the Join

Below is an updated approach to query your deals, ensuring that both criteria are met:

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

Explanation of the Updated Query

Joining Tables: We join the people table to the deals table based on the person_id foreign key. This ensures we're looking at the correct relationship data.

Combined Conditions: By using a closure within the where method:

We call the notFilled() method (from our Deal model) to check for empty fields.

We include an orWhereNull('people.email') check to ensure that any Deal associated with a Person that has a null email also appears in the results.

Sorting and Pagination: Finally, we sort the results based on the won_time and paginate the output, providing a manageable result size.

Conclusion

With this approach, you now effectively query your Deal records to include those with empty fields, as well as ensuring that any related Person lacks an email address. This two-pronged method gives you the flexibility needed to retrieve the exact data you require without missing crucial records.

If you have alternative methods or suggestions for improving the efficiency of this solution, feel free to share them in the comments!