Database Access with DAO & DTO

DVC provides a clean database abstraction through:

• DTO (Data Transfer Objects) - Single records
• DTO Set - Collections of DTOs
• DAO (Data Access Objects) - CRUD operations

Quick Start with SQLite

1. Initialize Configuration:

   mkdir -p src/data
   cp src/data/defaults-example.json src/data/defaults.json
   

2. Configure SQLite (src/data/defaults.json):

   {
     "db_type": "sqlite",
     "sqlite": {
       "fileName": "storage/database.db"
     }
   }
   

Core Concepts

1. DTO (Single Record)

// Auto-hydrated from database rows
$user = (new bravedave\dvc\dto)('SELECT * FROM users WHERE id = 1');
echo $user->name; // Access fields as properties

2. DTO Set (Record Collections)

$users = (new bravedave\dvc\dtoSet)('SELECT id, name FROM users');

foreach ($users as $user) {
    echo $user->name; // Each item is a DTO
}

3. DAO (Table Gateway)

class users extends bravedave\dvc\dao {
    protected $_db_name = 'users';
    protected $template = dto\users::class;
}

// Usage
$usersDao = new users();

CRUD Operations

Create

$newId = $usersDao->insert([
    'name' => 'Dave',
    'email' => 'dave@example.com'
]);

Read

// Get single record
$user = $usersDao->getByID(3);

// Get all records
$allUsers = $usersDao->getAll();

Update

// Update by ID
$usersDao->updateByID(
    ['name' => 'Dingo'], // Fields to update
    3                   // Record ID
);

Delete

$usersDao->delete(3); // By ID

Advanced Usage

Custom DTO Classes

namespace dto;

class users extends bravedave\dvc\dto {
    public function displayName() {
        return "User: {$this->name}";
    }
}

Why This Architecture?

1. DTO Benefits:

   • Type-safe record access
   • Custom business logic methods
   • Prevents "array soup" in code

2. DAO Advantages:

   • Single point of table access
   • Built-in CRUD operations
   • Easy to mock for testing

3. SQLite First:

   • Zero-config for development
   • File-based simplicity
   • Scales to MariaDB when needed

---

1. DAO/DTO Relationship:

classDiagram
  class DAO {
    +getByID()
  }
  class DTO {
    +__construct(rowData)
    +__invoke(SQL)
    +propertyAccess
  }
  class DTOSet {
    +__invoke(SQL)
  }
  DAO --> DTO: Returns
  DTOSet --> DTO: Contains