Class yii\caching\DbQueryDependency

Inheritance	yii\caching\DbQueryDependency » yii\caching\Dependency » yii\base\Object
Implements	yii\base\Configurable
Available since version	2.0.12
Source Code	https://github.com/yiisoft/yii2/blob/master/framework/caching/DbQueryDependency.php

DbQueryDependency represents a dependency based on the query result of an yii\db\QueryInterface instance.

If the query result changes, the dependency is considered as changed. The query is specified via the $query property.

Object of any class which matches yii\db\QueryInterface can be used, so this dependency can be used not only with regular relational databases but with MongoDB, Redis and so on as well.

For more details and usage information on Cache, see the guide article on caching.

See also yii\db\QueryInterface.

Public Properties

Property	Type	Description	Defined By
$data	mixed	The dependency data that is saved in cache and later is compared with the latest dependency data.	yii\caching\Dependency
$db	string|array|object	The application component ID of the database connection, connection object or its array configuration.	yii\caching\DbQueryDependency
$method	string|callable	Method which should be invoked in over the $query object.	yii\caching\DbQueryDependency
$query	yii\db\QueryInterface	The query which result is used to determine if the dependency has been changed.	yii\caching\DbQueryDependency
$reusable	boolean	Whether this dependency is reusable or not.	yii\caching\Dependency

Public Methods

Method	Description	Defined By
__call()	Calls the named method which is not a class method.	yii\base\Object
__construct()	Constructor.	yii\base\Object
__get()	Returns the value of an object property.	yii\base\Object
__isset()	Checks if a property is set, i.e. defined and not null.	yii\base\Object
__set()	Sets value of an object property.	yii\base\Object
__unset()	Sets an object property to null.	yii\base\Object
canGetProperty()	Returns a value indicating whether a property can be read.	yii\base\Object
canSetProperty()	Returns a value indicating whether a property can be set.	yii\base\Object
className()	Returns the fully qualified name of this class.	yii\base\Object
evaluateDependency()	Evaluates the dependency by generating and saving the data related with dependency.	yii\caching\Dependency
getHasChanged()	Returns a value indicating whether the dependency has changed.	yii\caching\Dependency
hasMethod()	Returns a value indicating whether a method is defined.	yii\base\Object
hasProperty()	Returns a value indicating whether a property is defined.	yii\base\Object
init()	Initializes the object.	yii\base\Object
isChanged()	Checks whether the dependency is changed	yii\caching\Dependency
resetReusableData()	Resets all cached data for reusable dependencies.	yii\caching\Dependency

Protected Methods

Method	Description	Defined By
generateDependencyData()	Generates the data needed to determine if dependency is changed.	yii\caching\DbQueryDependency
generateReusableHash()	Generates a unique hash that can be used for retrieving reusable dependency data.	yii\caching\Dependency

Property Details

$db public property

The application component ID of the database connection, connection object or its array configuration. This field can be left blank, allowing query to determine connection automatically.

public string|array|object $db = null

$method public property

Method which should be invoked in over the $query object.

If specified as a string an own query method with such name will be invoked, passing $db value as its first argument. For example: exists, all.

This field can be specified as a PHP callback of following signature:

function (QueryInterface $query, mixed $db) {
    //return mixed;
}

If not set - yii\db\QueryInterface::one() will be used.

public string|callable $method = null

$query public property

The query which result is used to determine if the dependency has been changed. Actual query method to be invoked is determined by $method.

public yii\db\QueryInterface $query = null

Method Details