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Yii model layer operation attributes and methods summary.
tableName – Set the table name corresponding to the Model, for example:
public function tableName(){return 'gshop_order_ext';}
rules – Set validation rules for each field in the Model
relations – Set association rules
attributeLabels – Set aliases for each field
safeAttributes – Set fields that can modify attributes
beforeValidate and afterValidate – functions executed before and after field validation, which need to return a true value
beforeSave and afterSave – records the functions executed before and after storage, and needs to return a true value
Secondly, the ORM in Yii uses AR, and there are several main operations, namely:
save – operation data
update – modify data
delete – delete data
validate – Validate data
When reading records, there are several methods:
findByPk – Find a record by primary key, the result is a single record
findByAttribute – Find a record by attribute, the result is a single record
findAllByAttributes – Find data by attributes, the result is a recordset
findAll – Find data through CDbCriteria object, the result is a record set *
There are two types of parameters received by the search method. The one without an asterisk accepts an array as a parameter, and the one with an asterisk receives a CDbCriteria object as a parameter. When using an object, more search conditions can be provided. An example is given below. :
$criteria = new CDbCriteria; // Create CDbCriteria object
$criteria->condition = 'title LIKE %' . 'php' . '%'; // Set query conditions
$criteria->order = 'createdTime DESC'; // Set sorting criteria
$criteria->limit = 10; //Limit the number of records
$criteria->select = 'id,title,content'; // Set the fields included in the result
$articles = Article::model()->findAll($criteria); //The result is an array, each element of which is a record object
Again, Yii adopts the LazyLoad loading method for related data by default, that is, it reads it only when needed. In this way, when we do not need the related data, Yii will not help us read it, which greatly speeds up the response. Speed. But there are also times when we need to associate data. For example, when reading an article, we need the category to which the article belongs. If we use LazyLoad, how many articles will there be and how many times will be queried, which is very inefficient. , then EagerLoad is needed, that is, reading all the data in the related table at one time.
For example:
$articles = Article::model()->with('category')->findAll();
Use with to read all the data of the related table at once. The settings of the related table are set in the relationship in the Model.
For example:
public function relations() { return array( 'category' => array(self::BELONGS_TO, 'Category', 'categoryId'), ); }
Very clear and concise.