Class CDbCacheDependency

CDbCacheDependency represents a dependency based on the query result of a SQL statement.

If the query result (a scalar) changes, the dependency is considered as changed. To specify the SQL statement, set CDbCacheDependency::$sql property. The CDbCacheDependency::$connectionID property specifies the ID of a CDbConnection application component. It is this DB connection that is used to perform the query.

CComponent

CCacheDependency implements ICacheDependency

CDbCacheDependency

Package: system\caching\dependencies
Copyright: 2008-2013 Yii Software LLC
License: http://www.yiiframework.com/license/
Author: Qiang Xue <qiang.xue@gmail.com>
Since: 1.0
Located at x2engine/framework/caching/dependencies/CDbCacheDependency.php

Methods summary
`public`	# `__construct( string $sql = null )` Constructor. Constructor. Parameters `$sql` `string` $sql the SQL statement whose result is used to determine if the dependency has been changed.
`public array`	# `__sleep( )` PHP sleep magic method. This method ensures that the database instance is set null because it contains resource handles. PHP sleep magic method. This method ensures that the database instance is set null because it contains resource handles. Returns `array`
`protected mixed`	# `generateDependentData( )` Generates the data needed to determine if dependency has been changed. This method returns the value of the global state. Generates the data needed to determine if dependency has been changed. This method returns the value of the global state. Returns `mixed` the data needed to determine if dependency has been changed. Throws `CException` if `CDbCacheDependency::$sql` is empty Overrides `CCacheDependency::generateDependentData()`
`protected CDbConnection`	# `getDbConnection( )` Returns `CDbConnection` the DB connection instance Throws `CException` if `CDbCacheDependency::$connectionID` does not point to a valid application component.

Methods inherited from CCacheDependency
`evaluateDependency(), getDependentData(), getHasChanged(), resetReusableData()`

Methods inherited from CComponent
`__call(), __get(), __isset(), __set(), __unset(), asa(), attachBehavior(), attachBehaviors(), attachEventHandler(), canGetProperty(), canSetProperty(), detachBehavior(), detachBehaviors(), detachEventHandler(), disableBehavior(), disableBehaviors(), enableBehavior(), enableBehaviors(), evaluateExpression(), getEventHandlers(), hasEvent(), hasEventHandler(), hasProperty(), raiseEvent()`

Properties summary
`public string`	`$connectionID`	`'db'`	# the ID of a `CDbConnection` application component. Defaults to 'db'. the ID of a `CDbConnection` application component. Defaults to 'db'.
`public string`	`$sql`		# the SQL statement whose result is used to determine if the dependency has been changed. Note, the SQL statement should return back a single value. the SQL statement whose result is used to determine if the dependency has been changed. Note, the SQL statement should return back a single value.
`public array`	`$params`		# parameters (name=>value) to be bound to the SQL statement specified by `CDbCacheDependency::$sql`. parameters (name=>value) to be bound to the SQL statement specified by `CDbCacheDependency::$sql`. Since 1.1.4

Properties inherited from CCacheDependency
`$reuseDependentData`

Magic properties inherited from CCacheDependency
`$dependentData, $hasChanged`

Packages

Classes

Class CDbCacheDependency

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