In Ruby on Rails, ActiveRecord simplifies working with databases, and where.not is a common way to filter out records based on a condition. However, in some cases, using excluding — introduced in Rails 7 — can be a better alternative. Here’s why.
What is where.not?
where.not is used to exclude records that meet a specific condition. For example, if you want to fetch all users except those with a certain email:
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User.where.not(email: 'example@domain.com')
This is useful for excluding records based on specific conditions.
What is excluding?
excluding allows you to exclude specific records from a query. For example, to fetch all users but exclude a specific user:
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user_to_exclude = User.find_by(email: 'example@domain.com')
users = User.excluding(user_to_exclude)
This query retrieves all users except the one with the email example@domain.com.
Excluding Multiple Records
If you need to exclude multiple specific records, you can pass an array of records to excluding. For instance:
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users_to_exclude = User.where(role: 'admin')
users = User.excluding(users_to_exclude)
This excludes all users with the role admin from the result set.
Another example of excluding multiple specific users could be:
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specific_users = User.where(email: ['user1@domain.com', 'user2@domain.com'])
users = User.excluding(specific_users)
Here, users with the emails user1@domain.com and user2@domain.com are excluded from the query result.
Why Use excluding?
- Excluding Specific Records:
excludingis ideal when you want to exclude particular records (like a specific user or a group of users) that you’ve already loaded. It can eliminate the need to construct complexwhere.notconditions. - Cleaner Queries:
excludingprovides a simpler and more readable way to exclude specific records. It eliminates the need to manage conditions manually in your queries.
When to Use where.not?
Use where.not when you need to exclude entire records based on a condition, like excluding users over a certain age or with a specific status.
While where.not is great for excluding records based on conditions, excluding provides a cleaner, more intuitive way to exclude specific records. If you’re using Rails 7+, consider using excluding when working with individual records or groups of records for better readability and maintainability.