Class yii\db\Expression
Inheritance | yii\db\Expression » yii\base\BaseObject |
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Implements | yii\base\Configurable, yii\db\ExpressionInterface |
Available since version | 2.0 |
Source Code | https://github.com/yiisoft/yii2/blob/master/framework/db/Expression.php |
Expression represents a DB expression that does not need escaping or quoting.
When an Expression object is embedded within a SQL statement or fragment, it will be replaced with the $expression property value without any DB escaping or quoting. For example,
$expression = new Expression('NOW()');
$now = (new \yii\db\Query)->select($expression)->scalar(); // SELECT NOW();
echo $now; // prints the current date
Expression objects are mainly created for passing raw SQL expressions to methods of yii\db\Query, yii\db\ActiveQuery, and related classes.
An expression can also be bound with parameters specified via $params.
Public Properties
Property | Type | Description | Defined By |
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$expression | string | The DB expression | yii\db\Expression |
$params | array | List of parameters that should be bound for this expression. | yii\db\Expression |
Public Methods
Method | Description | Defined By |
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__call() | Calls the named method which is not a class method. | yii\base\BaseObject |
__construct() | Constructor. | yii\db\Expression |
__get() | Returns the value of an object property. | yii\base\BaseObject |
__isset() | Checks if a property is set, i.e. defined and not null. | yii\base\BaseObject |
__set() | Sets value of an object property. | yii\base\BaseObject |
__toString() | String magic method. | yii\db\Expression |
__unset() | Sets an object property to null. | yii\base\BaseObject |
canGetProperty() | Returns a value indicating whether a property can be read. | yii\base\BaseObject |
canSetProperty() | Returns a value indicating whether a property can be set. | yii\base\BaseObject |
className() | Returns the fully qualified name of this class. | yii\base\BaseObject |
hasMethod() | Returns a value indicating whether a method is defined. | yii\base\BaseObject |
hasProperty() | Returns a value indicating whether a property is defined. | yii\base\BaseObject |
init() | Initializes the object. | yii\base\BaseObject |
Property Details
The DB expression
List of parameters that should be bound for this expression. The keys are placeholders appearing in $expression and the values are the corresponding parameter values.
Method Details
Constructor.
public void __construct ( $expression, $params = [], $config = [] ) | ||
$expression | string | The DB expression |
$params | array | Parameters |
$config | array | Name-value pairs that will be used to initialize the object properties |
String magic method.
public string __toString ( ) | ||
return | string | The DB expression. |
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