**Course Title:** Mastering Yii Framework: Building Scalable Web Applications **Section Title:** Database Management with Active Record **Topic:** Performing CRUD operations using Active Record **Overview** In this topic, we will explore how to perform Create, Read, Update, and Delete (CRUD) operations using Yii's Active Record. Active Record is a powerful ORM (Object-Relational Mapping) tool that allows you to interact with your database using PHP objects. By the end of this topic, you will be able to perform CRUD operations on your database using Active Record. **What is Active Record?** Active Record is a design pattern that maps a database table to a PHP class. This class represents a row in the table and provides methods to interact with the row. Active Record is a key component of Yii's database management system. **CRUD Operations using Active Record** ### Create (Insert) To create a new record in the database, you can use the `save()` method of the Active Record class. Here is an example: ```php // Create a new User object $user = new User(); // Set the user's attributes $user->name = 'John Doe'; $user->email = 'john@example.com'; // Save the user to the database $user->save(); ``` In this example, we create a new `User` object and set its attributes using the object's properties. We then call the `save()` method to save the user to the database. ### Read (Select) To retrieve a record from the database, you can use the `find()` method of the Active Record class. Here is an example: ```php // Find a user by ID $user = User::findOne(1); // Print the user's name echo $user->name; ``` In this example, we use the `findOne()` method to find a user by ID. We then print the user's name using the object's properties. ### Update (Edit) To update a record in the database, you can use the `update()` method of the Active Record class. Here is an example: ```php // Find a user by ID $user = User::findOne(1); // Update the user's name $user->name = 'Jane Doe'; // Save the changes to the database $user->save(); ``` In this example, we find a user by ID and update its name. We then call the `save()` method to save the changes to the database. ### Delete (Delete) To delete a record from the database, you can use the `delete()` method of the Active Record class. Here is an example: ```php // Find a user by ID $user = User::findOne(1); // Delete the user from the database $user->delete(); ``` In this example, we find a user by ID and call the `delete()` method to delete the user from the database. **Best Practices** When performing CRUD operations using Active Record, follow these best practices: * Always use the `findOne()` method to retrieve a single record from the database. * Use the `save()` method to save changes to the database. * Use the `update()` method to update a record in the database. * Use the `delete()` method to delete a record from the database. * Always validate user input before saving it to the database. **Conclusion** In this topic, we explored how to perform CRUD operations using Yii's Active Record. We covered the basics of Active Record, including how to create, read, update, and delete records in the database. We also discussed best practices for using Active Record in your applications. **What's Next?** In the next topic, we will explore how to understand relations in Active Record, including one-to-one, one-to-many, and many-to-many relationships. **Leave a comment or ask for help** If you have any questions or need help with implementing Active Record in your applications, please leave a comment below.