ExplainAction

API reference › Debug › actions › db › ExplainAction

class	`yii\debug\actions\db\ExplainAction`
Extends	`yii\debug\actions\Action` » `yii\web\Action` » `yii\base\Action` » `yii\base\Component` » `yii\base\BaseObject`
Implements	`yii\base\ViewContextInterface`, `yii\base\Configurable`
Source	`src/actions/db/ExplainAction.php`

Renders the EXPLAIN plan for a single captured SQL query.

Maps to the db-explain route registered by DbPanel::init(); consumes tag (request snapshot) and seq (the captured row’s own sequence number) to locate the SQL statement and execute the driver-appropriate EXPLAIN command. Malformed input answers 400 and an unknown tag or sequence answers 404, both with an empty body, so the inline AJAX workflow never renders an exception page inside the grid.

SQLite uses EXPLAIN QUERY PLAN; MySQL and PostgreSQL use plain EXPLAIN. Statements that produce no useful plan and database rejections are handled as successful diagnostic responses so the captured query and the escaped reason replace the result instead of a generic transport failure.

Properties

Property	Type	Description	Defined by
`$behaviors` read-only	`array<yii\base\Behavior<static>>`	List of behaviors attached to this component.	`yii\base\Component`
`$controller`	`yii\base\T\|null`	The controller that owns this action, or `null` when the action runs standalone. via `Module::$actionMap` Default: `null`.	`yii\base\Action`
`$debugModule` read-only	`yii\debug\Module`	Owning debug module.	`yii\debug\actions\Action`
`$id`	`string\|null`	ID of the action; `null` between construction and dispatcher post-assignment for standalone actions resolved through `Module::$actionMap` or `Module::$actionNamespace`. Default: `null`.	`yii\base\Action`
`$manifest` read-only	`array<string, PHPForge\Debug\Storage\RequestSummary>`	Manifest entries indexed by tag.	`yii\debug\actions\Action`
`$module`	`yii\base\Module\|null`	The owning module, or `null` if neither a module nor a controller is attached. Available since 22.0.	`yii\base\Action`
`$summary`	`PHPForge\Debug\Storage\RequestSummary\|null`	Summary metadata for the active debug entry, populated by `loadData()`. Default: `null`.	`yii\debug\actions\Action`
`$uniqueId` read-only	`string`	The unique ID of this action among the whole application.	`yii\base\Action`
`$viewPath` read-only	`string`	Absolute path to the debugger views.	`yii\debug\actions\Action`

Methods

Method	Description	Defined by
`__construct()`	Constructor.	`yii\base\Action`
`__call()`	Calls the named method which is not a class method.	`yii\base\Component`
`__clone()`	This method is called after the object is created by cloning an existing one.	`yii\base\Component`
`__get()`	Returns the value of a component property.	`yii\base\Component`
`__isset()`	Checks if a property is set, i.e. defined and not null.	`yii\base\Component`
`__set()`	Sets the value of a component property.	`yii\base\Component`
`__unset()`	Sets a component property to be null.	`yii\base\Component`
`attachBehavior()`	Attaches a behavior to this component.	`yii\base\Component`
`attachBehaviors()`	Attaches a list of behaviors to the component.	`yii\base\Component`
`behaviors()`	Returns a list of behaviors that this component should behave as.	`yii\base\Component`
`canGetProperty()`	Returns a value indicating whether a property can be read.	`yii\base\Component`
`canSetProperty()`	Returns a value indicating whether a property can be set.	`yii\base\Component`
`className()` static	Returns the fully qualified name of this class.	`yii\base\BaseObject`
`detachBehavior()`	Detaches a behavior from the component.	`yii\base\Component`
`detachBehaviors()`	Detaches all behaviors from the component.	`yii\base\Component`
`ensureBehaviors()`	Makes sure that the behaviors declared in `behaviors()` are attached to this component.	`yii\base\Component`
`getBehavior()`	Returns the named behavior object.	`yii\base\Component`
`getBehaviors()`	Returns all behaviors attached to this component.	`yii\base\Component`
`getDebugModule()`	Returns the owning debug module.	`yii\debug\actions\Action`
`getManifest()`	Returns the debug entry manifest, reloading it from the log target on demand.	`yii\debug\actions\Action`
`getModule()`	Returns the module that owns this action when invoked standalone.	`yii\base\Action`
`getUniqueId()`	Returns the unique ID of this action among the whole application.	`yii\base\Action`
`getViewPath()`	Returns the view directory shared by every debugger page.	`yii\debug\actions\Action`
`hasEventHandlers()`	Returns a value indicating whether there is any handler attached to the named event.	`yii\base\Component`
`hasMethod()`	Returns a value indicating whether a method is defined.	`yii\base\Component`
`hasProperty()`	Returns a value indicating whether a property is defined for this component.	`yii\base\Component`
`init()`	Initializes the object.	`yii\base\BaseObject`
`loadData()`	Loads the debug entry for the given tag into every registered panel.	`yii\debug\actions\Action`
`off()`	Detaches an existing event handler from this component.	`yii\base\Component`
`on()`	Attaches an event handler to an event.	`yii\base\Component`
`prepareShell()`	Prepares the shared shell for a request panel or nested panel action.	`yii\debug\actions\Action`
`render()`	Renders a debugger view wrapped in the shared page layout.	`yii\debug\actions\Action`
`renderPartial()`	Renders a debugger view without the page layout.	`yii\debug\actions\Action`
`run()`	Runs the action.	`ExplainAction`
`runWithParams()`	Runs this action with the specified parameters.	`yii\base\Action`
`setModule()`	Sets the module that owns this action when invoked standalone.	`yii\base\Action`
`trigger()`	Triggers an event.	`yii\base\Component`
`afterRun()` protected	This method is called right after `run()` is executed.	`yii\base\Action`
`beforeRun()` protected	Forces the HTML response format and installs the bare shell before the action body runs.	`yii\debug\actions\Action`
`createBareShellContext()` protected	Builds the bare shell installed by `beforeRun()` through `Module::getShellContextFactory()`.	`yii\debug\actions\Action`
`createPanelRenderContext()` protected	Builds the portable state available to shared panel renderers for the active snapshot.	`yii\debug\actions\Action`
`createShellContext()` protected	Builds the shared shell for an index or view page through `Module::getShellContextFactory()`.	`yii\debug\actions\Action`
`getLogTarget()` protected	Returns the initialized debug log target.	`yii\debug\actions\Action`
`getMailCollector()` protected	Returns the registered mail collector.	`yii\debug\actions\Action`
`getPanel()` protected	Returns a registered panel by ID.	`yii\debug\actions\Action`
`prepareIndexShell()` protected	Prepares the shared shell for the request history page.	`yii\debug\actions\Action`
`renderPanelError()` protected	Renders a JSON-safe panel exception snapshot through Yii’s exception view.	`yii\debug\actions\Action`
`resolveStandaloneParams()` protected	Resolves the parameters of `run()` using the same HTTP-aware binder as `Controller::bindActionParams()`.	`yii\web\Action`
`resolveTheme()` protected	Resolves the effective light or dark theme.	`yii\debug\actions\Action`

Method details

run()

public function run(mixed $seq, mixed $tag, yii\debug\panels\DbPanel $panel): string

Runs the action.

Parameters

Parameter	Type	Description
`$seq`	`mixed`	Sequence number of the captured row to explain; anything but a digit string answers `400`.
`$tag`	`mixed`	Request tag whose debug snapshot holds the query; anything but a non-empty string answers `400`.
`$panel`	`yii\debug\panels\DbPanel`	Panel instance resolved from the debug module’s service locator by the standalone-action binder.

Returns

string: Rendered view with the EXPLAIN results, or '' for the 400 and 404 responses.