Yii2 数据库Active Record(ORM)

ACTIVE RECORD(ORM)

参考:http://www.yiiframework.com/doc-2.0/guide-db-active-record.html

1. namespace app\models;
2. use yii\db\ActiveRecord;
3. class Customer extends ActiveRecord
4. {
5. const STATUS_ACTIVE = 'active';
6. const STATUS_DELETED = 'deleted';
7. public static function tableName()
8. {
9. return 'customer';
10. }
11. public static function getDb()
12. {
13. return \Yii::$app->db2;  // use the "db2" application component
14. }
15. public static function init() //自定义初始默认数据
16. {
17. parent::init();
18. $this->status = self::STATUS_ACTIVE;
19. }
20. }

访问数据列

1. $id = $customer->id;
2. $email = $customer->email;
3. -------------
4. $customer->email = 'jane@example.com';
5. $customer->save();

查询数据

1. $customers = Customer::find()
2. ->where(['status' => Customer::STATUS_ACTIVE])
3. ->orderBy('id')
4. ->all();
5. $customer = Customer::find()
6. ->where(['id' => 1])
7. ->one();
8. $count = Customer::find()
9. ->where(['status' => Customer::STATUS_ACTIVE])
10. ->count();
11. $customers = Customer::find()->indexBy('id')->all();
12. $sql = 'SELECT * FROM customer';
13. $customers = Customer::findBySql($sql)->all();
14. // to return a single customer whose ID is 1:
15. $customer = Customer::findOne(1);
16. Customer::find()->where(['status' => Customer::STATUS_ACTIVE])->limit(1)->one()
17. //返回数组
18. $customers = Customer::find()
19. ->asArray()
20. ->all();

批量返回

1. // fetch 10 customers at a time
2. foreach (Customer::find()->batch(10) as $customers) {
3. // $customers is an array of 10 or fewer Customer objects
4. }
5. // fetch 10 customers at a time and iterate them one by one
6. foreach (Customer::find()->each(10) as $customer) {
7. // $customer is a Customer object
8. }
9. // batch query with eager loading
10. foreach (Customer::find()->with('orders')->each() as $customer) {
11. }

数据处理

• save()
• insert()
• update()
• delete()

批量数据处理

• updateCounters()
• updateAll()
• updateAllCounters()
• deleteAll()

1. // to insert a new customer record
2. $customer = new Customer();
3. $customer->name = 'James';
4. $customer->email = 'james@example.com';
5. $customer->save();  // equivalent to $customer->insert();
6. // to update an existing customer record
7. $customer = Customer::findOne($id);
8. $customer->email = 'james@example.com';
9. $customer->save();  // equivalent to $customer->update();
10. // to delete an existing customer record
11. $customer = Customer::findOne($id);
12. $customer->delete();
13. // to delete several customers
14. Customer::deleteAll('age > :age AND gender = :gender', [':age' => 20, ':gender' => 'M']);
15. // to increment the age of ALL customers by 1
16. Customer::updateAllCounters(['age' => 1]);

数据效验

1. $model = Customer::findOne($id);
2. if ($model === null) {
3. throw new NotFoundHttpException;
4. }
5. if ($model->load(Yii::$app->request->post()) && $model->save()) {
6. // the user input has been collected, validated and saved
7. }else{
8. ;
9. }

初始默认数据

1. $customer = new Customer();
2. $customer->loadDefaultValues();

生命与执行周期

初始化

1. constructor
2. init(): will trigger an EVENT_INIT event

调用 save()时

1. beforeValidate(): //return bool
2. afterValidate(): will trigger an EVENT_AFTER_VALIDATE event
3. beforeSave(): will trigger an EVENT_BEFORE_INSERT or EVENT_BEFORE_UPDATE event
4. perform the actual data insertion or updating
5. afterSave(): will trigger an EVENT_AFTER_INSERT or EVENT_AFTER_UPDATE event

调用delete()删除时

1. beforeDelete(): will trigger an EVENT_BEFORE_DELETE event
2. perform the actual data deletion
3. afterDelete(): will trigger an EVENT_AFTER_DELETE event

关联表数据

yii\db\ActiveRecord::hasMany() and yii\db\ActiveRecord::hasOne()

1. class Customer extends \yii\db\ActiveRecord
2. {
3. public function getOrders()
4. {
5. // Customer has_many Order via Order.customer_id -> id
6. return $this->hasMany(Order::className(), ['customer_id' => 'id']);
7. }
8. }
9. class Order extends \yii\db\ActiveRecord
10. {
11. public function getCustomer()
12. {
13. // Order has_one Customer via Customer.id -> customer_id
14. return $this->hasOne(Customer::className(), ['id' => 'customer_id']);
15. }
16. }
17. class Customer extends \yii\db\ActiveRecord
18. {
19. public function getBigOrders($threshold = 100)
20. {
21. return $this->hasMany(Order::className(), ['customer_id' => 'id'])
22. ->where('subtotal > :threshold', [':threshold' => $threshold])
23. ->orderBy('id');
24. }
25. }
26. $orders = $customer->getBigOrders(200)->all();

中间关联表
via() or viaTable()

1. class Order extends \yii\db\ActiveRecord
2. {
3. public function getItems()
4. {
5. return $this->hasMany(Item::className(), ['id' => 'item_id'])
6. ->viaTable('order_item', ['order_id' => 'id']);
7. }
8. }

贪婪模式

1. // SQL executed: SELECT * FROM customer WHERE id=1
2. $customer = Customer::findOne(1);
3. // SQL executed: SELECT * FROM order WHERE customer_id=1
4. $orders = $customer->orders;
5. // no SQL executed
6. $orders2 = $customer->orders;
7. ------------
8. $customers = Customer::find()->limit(100)->all();
9. foreach ($customers as $customer) {
10. // SQL executed: SELECT * FROM order WHERE customer_id=...
11. $orders = $customer->orders;
12. // ...handle $orders...
13. }
14. ---------------
15. // SQL executed: SELECT * FROM customer LIMIT 100;
16. //               SELECT * FROM orders WHERE customer_id IN (1,2,...)
17. $customers = Customer::find()->limit(100)
18. ->with('orders')->all();
19. foreach ($customers as $customer) {
20. // no SQL executed
21. $orders = $customer->orders;
22. // ...handle $orders...
23. }
24. -----------------------
25. $customer = Customer::findOne(1);
26. // lazy loading: SELECT * FROM order WHERE customer_id=1 AND subtotal>100
27. $orders = $customer->getOrders()->where('subtotal>100')->all();
28. // eager loading: SELECT * FROM customer LIMIT 100
29. //                SELECT * FROM order WHERE customer_id IN (1,2,...) AND subtotal>100
30. $customers = Customer::find()->limit(100)->with([
31. 'orders' => function($query) {
32. $query->andWhere('subtotal>100');
33. },
34. ])->all();

联合查询关联表

1. // join with multiple relations
2. // find the orders that contain books and were placed by customers who registered within the past 24 hours
3. $orders = Order::find()->innerJoinWith([
4. 'books',
5. 'customer' => function ($query) {
6. $query->where('customer.created_at > ' . (time() - 24 * 3600));
7. }
8. ])->all();
9. // join with sub-relations: join with books and books' authors
10. $orders = Order::find()->joinWith('books.author')->all();
11. class User extends ActiveRecord
12. {
13. public function getBooks()
14. {
15. return $this->hasMany(Item::className(), ['owner_id' => 'id'])->onCondition(['category_id' => 1]);
16. }
17. }
18. // SELECT user.* FROM user LEFT JOIN item ON item.owner_id=user.id AND category_id=1
19. // SELECT * FROM item WHERE owner_id IN (...) AND category_id=1
20. $users = User::find()->joinWith('books')->all();
21. // find all orders that contain books, but do not eager load "books".
22. $orders = Order::find()->innerJoinWith('books', false)->all();
23. // which is equivalent to the above
24. $orders = Order::find()->joinWith('books', false, 'INNER JOIN')->all()
25. //额外条件
26. class User extends ActiveRecord
27. {
28. public function getBooks()
29. {
30. return $this->hasMany(Item::className(), ['owner_id' => 'id'])->onCondition(['category_id' => 1]);
31. }
32. }

操作关系
link() and unlink()

1. $customer = Customer::findOne(1);
2. $order = new Order();
3. $order->subtotal = 100;
4. $customer->link('orders', $order);
5. $customer->save();

Cross-DBMS

1. // Relational database Active Record
2. class Customer extends \yii\db\ActiveRecord
3. {
4. public static function tableName()
5. {
6. return 'customer';
7. }
8. public function getComments()
9. {
10. // Customer, stored in relational database, has many Comments, stored in MongoDB collection:
11. return $this->hasMany(Comment::className(), ['customer_id' => 'id']);
12. }
13. }
14. // MongoDb Active Record
15. class Comment extends \yii\mongodb\ActiveRecord
16. {
17. public static function collectionName()
18. {
19. return 'comment';
20. }
21. public function getCustomer()
22. {
23. // Comment, stored in MongoDB collection, has one Customer, stored in relational database:
24. return $this->hasOne(Customer::className(), ['id' => 'customer_id']);
25. }
26. }

过滤

1. namespace app\models;
2. use yii\db\ActiveQuery;
3. class CommentQuery extends ActiveQuery
4. {
5. public function active($state = true)
6. {
7. $this->andWhere(['active' => $state]);
8. return $this;
9. }
10. }
11. namespace app\models;
12. use yii\db\ActiveRecord;
13. class Comment extends ActiveRecord
14. {
15. /**
16. * @inheritdoc
17. * @return CommentQuery
18. */
19. public static function find()
20. {
21. return new CommentQuery(get_called_class());
22. }
23. }
24. $comments = Comment::find()->active()->all();
25. $inactiveComments = Comment::find()->active(false)->all();
26. class Post extends \yii\db\ActiveRecord
27. {
28. public function getActiveComments()
29. {
30. return $this->hasMany(Comment::className(), ['post_id' => 'id'])->active();
31. }
32. }
33. $posts = Post::find()->with([
34. 'comments' => function($q) {
35. $q->active();
36. }
37. ])->all();
38. //默认
39. public static function find()
40. {
41. return parent::find()->where(['deleted' => false]);
42. }

事务

1. class Post extends \yii\db\ActiveRecord
2. {
3. public function transactions()
4. {
5. return [
6. 'admin' => self::OP_INSERT,
7. 'api' => self::OP_INSERT | self::OP_UPDATE | self::OP_DELETE,
8. // the above is equivalent to the following:
9. // 'api' => self::OP_ALL,
10. ];
11. }
12. }

1. $model=Post::model();
2. $transaction=$model->dbConnection->beginTransaction();
3. try
4. {
5. // 查找和保存是可能由另一个请求干预的两个步骤
6. // 这样我们使用一个事务以确保其一致性和完整性
7. $post=$model->findByPk(10);
8. $post->title='new post title';
9. $post->save();
10. $transaction->commit();
11. }
12. catch(Exception $e)
13. {
14. $transaction->rollBack();
15. }