在 Laravel 6 中删除嵌套的关联模型,跨多个数据库连接的情况下

1、查询关联时嵌套预加载的实现

$wpThemes = Theme::with(['themeInstallation.themeInstallationVersionPreset.themeInstallationTasks' => function ($query) {
            $query->orderBy('id', 'desc');
        }])->withCount(['logs'])->orderBy('updated_at_gmt', 'desc')->get()->makeHidden('content')->toArray();

2、打印执行的 SQL 语句

select
  `wp_themes`.*,
  (
    select
      count(*)
    from
      `wp_theme_logs`
    where
      `wp_themes`.`id` = `wp_theme_logs`.`theme_id`
  ) as `logs_count`
from
  `wp_themes`
order by
  `updated_at_gmt` desc;

select
  *
from
  `theme_installation`
where
  `theme_installation`.`wp_theme_id` in (
    1,
    2,
    3,
    4,
    5,
    135,
    136,
    137,
    140,
    141,
    142,
    143,
    144,
    145,
    146,
    147,
    148,
    149,
    150,
    151,
    152,
    153,
    154,
    155,
    156,
    157,
    158
  );

select
  *
from
  `theme_installation_version_preset`
where
  `theme_installation_version_preset`.`theme_installation_id` in (
    27,
    30,
    31,
    32,
    33,
    34,
    35,
    36,
    37,
    38,
    39,
    40,
    41,
    42,
    43,
    44,
    45,
    46,
    47,
    48
  );

select
  *
from
  `theme_installation_task`
where
  `theme_installation_task`.`theme_installation_version_preset_id` in (
    27,
    30,
    31,
    32,
    33,
    34,
    35,
    36,
    37,
    38,
    39,
    40,
    41,
    42,
    43,
    44,
    45,
    46,
    47,
    48
  )
order by
  `id` desc;

3、现在计划删除 wp_themes 表中的一条记录时,删除嵌套的关联模型(总计涉及到 3 个关联模型)。为何不在表之间设置级联外键关系,以便 DBMS 自动删除相关行,原因在于 wp_themes 在 A 数据库中,而 3 个关联模型在 B 数据库中。

4、最终实现如下

$theme = findOrFail($id);
$theme->themeInstallation->themeInstallationVersionPreset->themeInstallationTasks()->delete();
$theme->themeInstallation->themeInstallationVersionPreset()->delete();
$theme->themeInstallation()->delete();
$theme->delete();

5、执行时报错:SQLSTATE[42S02]: Base table or view not found: 1146 Table ‘object_store.themes’ doesn’t exist (SQL: delete from `themes` where `id` = 156) 。提示:wp_themes 在 B 数据库中不存在。实则 wp_themes 应该在 A 数据库中的。报错所在行:$theme->delete(); 。虽然关联的 3 个模型已经被成功删除。如图1

图1

{
    "message": "SQLSTATE[42S02]: Base table or view not found: 1146 Table 'object_store.themes' doesn't exist (SQL: delete from `themes` where `id` = 156)",
    "code": "42S02",
    "status_code": 500,
    "debug": {
        "line": 669,
        "file": "E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php",
        "class": "Illuminate\\Database\\QueryException",
        "trace": {
            "previous": [
                "#0 E:\\wwwroot\\object\\vendor\\doctrine\\dbal\\lib\\Doctrine\\DBAL\\Driver\\PDOConnection.php(87): Doctrine\\DBAL\\Driver\\PDO\\Exception::new(Object(PDOException))",
                "#1 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php(484): Doctrine\\DBAL\\Driver\\PDOConnection->prepare('delete from `th...')",
                "#2 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php(662): Illuminate\\Database\\Connection->Illuminate\\Database\\{closure}('delete from `th...', Array)",
                "#3 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php(629): Illuminate\\Database\\Connection->runQueryCallback('delete from `th...', Array, Object(Closure))",
                "#4 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php(495): Illuminate\\Database\\Connection->run('delete from `th...', Array, Object(Closure))",
                "#5 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php(440): Illuminate\\Database\\Connection->affectingStatement('delete from `th...', Array)",
                "#6 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Query\\Builder.php(2823): Illuminate\\Database\\Connection->delete('delete from `th...', Array)",
                "#7 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Eloquent\\Builder.php(874): Illuminate\\Database\\Query\\Builder->delete()",
                "#8 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Eloquent\\Model.php(936): Illuminate\\Database\\Eloquent\\Builder->delete()",
                "#9 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Eloquent\\Model.php(907): Illuminate\\Database\\Eloquent\\Model->performDeleteOnModel()",
                "#10 E:\\wwwroot\\object\\app\\Services\\ThemeService.php(198): Illuminate\\Database\\Eloquent\\Model->delete()",
                "#11 E:\\wwwroot\\object\\app\\Http\\Controllers\\Admin\\API\\ThemeController.php(165): App\\Services\\ThemeService->delete(156)",
                "#12 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Controller.php(54): App\\Http\\Controllers\\Admin\\API\\ThemeController->destroy('156', Object(App\\Services\\ThemeService))",
                "#13 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\ControllerDispatcher.php(45): Illuminate\\Routing\\Controller->callAction('destroy', Array)",
                "#14 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Route.php(219): Illuminate\\Routing\\ControllerDispatcher->dispatch(Object(Illuminate\\Routing\\Route), Object(App\\Http\\Controllers\\Admin\\API\\ThemeController), 'destroy')",
                "#15 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Route.php(176): Illuminate\\Routing\\Route->runController()",
                "#16 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(681): Illuminate\\Routing\\Route->run()",
                "#17 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(130): Illuminate\\Routing\\Router->Illuminate\\Routing\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#18 E:\\wwwroot\\object\\vendor\\spatie\\laravel-permission\\src\\Middlewares\\RoleOrPermissionMiddleware.php(25): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#19 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Spatie\\Permission\\Middlewares\\RoleOrPermissionMiddleware->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure), 'manage_themes|a...')",
                "#20 E:\\wwwroot\\object\\app\\Http\\Middleware\\CheckStoreAdminStatus.php(45): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#21 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): App\\Http\\Middleware\\CheckStoreAdminStatus->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#22 E:\\wwwroot\\object\\app\\Http\\Middleware\\SwitchLanguage.php(28): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#23 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): App\\Http\\Middleware\\SwitchLanguage->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#24 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\Auth.php(55): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#25 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Dingo\\Api\\Http\\Middleware\\Auth->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#26 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Auth\\Middleware\\Authenticate.php(43): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#27 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Auth\\Middleware\\Authenticate->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure), 'api')",
                "#28 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\PrepareController.php(45): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#29 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Dingo\\Api\\Http\\Middleware\\PrepareController->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#30 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(105): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#31 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(683): Illuminate\\Pipeline\\Pipeline->then(Object(Closure))",
                "#32 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(658): Illuminate\\Routing\\Router->runRouteWithinStack(Object(Illuminate\\Routing\\Route), Object(Dingo\\Api\\Http\\Request))",
                "#33 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(624): Illuminate\\Routing\\Router->runRoute(Object(Dingo\\Api\\Http\\Request), Object(Illuminate\\Routing\\Route))",
                "#34 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(613): Illuminate\\Routing\\Router->dispatchToRoute(Object(Dingo\\Api\\Http\\Request))",
                "#35 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Routing\\Adapter\\Laravel.php(88): Illuminate\\Routing\\Router->dispatch(Object(Dingo\\Api\\Http\\Request))",
                "#36 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Routing\\Router.php(518): Dingo\\Api\\Routing\\Adapter\\Laravel->dispatch(Object(Dingo\\Api\\Http\\Request), 'v1')",
                "#37 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\Request.php(126): Dingo\\Api\\Routing\\Router->dispatch(Object(Dingo\\Api\\Http\\Request))",
                "#38 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(130): Dingo\\Api\\Http\\Middleware\\Request->Dingo\\Api\\Http\\Middleware\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#39 E:\\wwwroot\\object\\app\\Http\\Middleware\\ChangeAppUrlMiddleware.php(23): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#40 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): App\\Http\\Middleware\\ChangeAppUrlMiddleware->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#41 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest.php(21): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#42 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#43 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest.php(21): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#44 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#45 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Middleware\\ValidatePostSize.php(27): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#46 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Foundation\\Http\\Middleware\\ValidatePostSize->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#47 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Middleware\\CheckForMaintenanceMode.php(63): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#48 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Foundation\\Http\\Middleware\\CheckForMaintenanceMode->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#49 E:\\wwwroot\\object\\vendor\\fideloper\\proxy\\src\\TrustProxies.php(57): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#50 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Fideloper\\Proxy\\TrustProxies->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#51 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(105): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#52 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\Request.php(127): Illuminate\\Pipeline\\Pipeline->then(Object(Closure))",
                "#53 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\Request.php(103): Dingo\\Api\\Http\\Middleware\\Request->sendRequestThroughRouter(Object(Dingo\\Api\\Http\\Request))",
                "#54 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Dingo\\Api\\Http\\Middleware\\Request->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#55 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(105): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Illuminate\\Http\\Request))",
                "#56 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Kernel.php(145): Illuminate\\Pipeline\\Pipeline->then(Object(Closure))",
                "#57 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Kernel.php(110): Illuminate\\Foundation\\Http\\Kernel->sendRequestThroughRouter(Object(Illuminate\\Http\\Request))",
                "#58 E:\\wwwroot\\object\\public\\index.php(57): Illuminate\\Foundation\\Http\\Kernel->handle(Object(Illuminate\\Http\\Request))",
                "#59 {main}"
            ],
            "current": [
                "#0 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php(629): Illuminate\\Database\\Connection->runQueryCallback('delete from `th...', Array, Object(Closure))",
                "#1 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php(495): Illuminate\\Database\\Connection->run('delete from `th...', Array, Object(Closure))",
                "#2 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Connection.php(440): Illuminate\\Database\\Connection->affectingStatement('delete from `th...', Array)",
                "#3 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Query\\Builder.php(2823): Illuminate\\Database\\Connection->delete('delete from `th...', Array)",
                "#4 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Eloquent\\Builder.php(874): Illuminate\\Database\\Query\\Builder->delete()",
                "#5 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Eloquent\\Model.php(936): Illuminate\\Database\\Eloquent\\Builder->delete()",
                "#6 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Database\\Eloquent\\Model.php(907): Illuminate\\Database\\Eloquent\\Model->performDeleteOnModel()",
                "#7 E:\\wwwroot\\object\\app\\Services\\ThemeService.php(198): Illuminate\\Database\\Eloquent\\Model->delete()",
                "#8 E:\\wwwroot\\object\\app\\Http\\Controllers\\Admin\\API\\ThemeController.php(165): App\\Services\\ThemeService->delete(156)",
                "#9 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Controller.php(54): App\\Http\\Controllers\\Admin\\API\\ThemeController->destroy('156', Object(App\\Services\\ThemeService))",
                "#10 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\ControllerDispatcher.php(45): Illuminate\\Routing\\Controller->callAction('destroy', Array)",
                "#11 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Route.php(219): Illuminate\\Routing\\ControllerDispatcher->dispatch(Object(Illuminate\\Routing\\Route), Object(App\\Http\\Controllers\\Admin\\API\\ThemeController), 'destroy')",
                "#12 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Route.php(176): Illuminate\\Routing\\Route->runController()",
                "#13 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(681): Illuminate\\Routing\\Route->run()",
                "#14 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(130): Illuminate\\Routing\\Router->Illuminate\\Routing\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#15 E:\\wwwroot\\object\\vendor\\spatie\\laravel-permission\\src\\Middlewares\\RoleOrPermissionMiddleware.php(25): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#16 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Spatie\\Permission\\Middlewares\\RoleOrPermissionMiddleware->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure), 'manage_themes|a...')",
                "#17 E:\\wwwroot\\object\\app\\Http\\Middleware\\CheckStoreAdminStatus.php(45): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#18 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): App\\Http\\Middleware\\CheckStoreAdminStatus->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#19 E:\\wwwroot\\object\\app\\Http\\Middleware\\SwitchLanguage.php(28): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#20 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): App\\Http\\Middleware\\SwitchLanguage->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#21 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\Auth.php(55): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#22 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Dingo\\Api\\Http\\Middleware\\Auth->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#23 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Auth\\Middleware\\Authenticate.php(43): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#24 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Auth\\Middleware\\Authenticate->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure), 'api')",
                "#25 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\PrepareController.php(45): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#26 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Dingo\\Api\\Http\\Middleware\\PrepareController->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#27 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(105): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#28 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(683): Illuminate\\Pipeline\\Pipeline->then(Object(Closure))",
                "#29 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(658): Illuminate\\Routing\\Router->runRouteWithinStack(Object(Illuminate\\Routing\\Route), Object(Dingo\\Api\\Http\\Request))",
                "#30 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(624): Illuminate\\Routing\\Router->runRoute(Object(Dingo\\Api\\Http\\Request), Object(Illuminate\\Routing\\Route))",
                "#31 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Routing\\Router.php(613): Illuminate\\Routing\\Router->dispatchToRoute(Object(Dingo\\Api\\Http\\Request))",
                "#32 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Routing\\Adapter\\Laravel.php(88): Illuminate\\Routing\\Router->dispatch(Object(Dingo\\Api\\Http\\Request))",
                "#33 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Routing\\Router.php(518): Dingo\\Api\\Routing\\Adapter\\Laravel->dispatch(Object(Dingo\\Api\\Http\\Request), 'v1')",
                "#34 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\Request.php(126): Dingo\\Api\\Routing\\Router->dispatch(Object(Dingo\\Api\\Http\\Request))",
                "#35 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(130): Dingo\\Api\\Http\\Middleware\\Request->Dingo\\Api\\Http\\Middleware\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#36 E:\\wwwroot\\object\\app\\Http\\Middleware\\ChangeAppUrlMiddleware.php(23): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#37 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): App\\Http\\Middleware\\ChangeAppUrlMiddleware->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#38 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest.php(21): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#39 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#40 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest.php(21): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#41 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#42 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Middleware\\ValidatePostSize.php(27): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#43 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Foundation\\Http\\Middleware\\ValidatePostSize->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#44 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Middleware\\CheckForMaintenanceMode.php(63): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#45 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Illuminate\\Foundation\\Http\\Middleware\\CheckForMaintenanceMode->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#46 E:\\wwwroot\\object\\vendor\\fideloper\\proxy\\src\\TrustProxies.php(57): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#47 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Fideloper\\Proxy\\TrustProxies->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#48 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(105): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Dingo\\Api\\Http\\Request))",
                "#49 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\Request.php(127): Illuminate\\Pipeline\\Pipeline->then(Object(Closure))",
                "#50 E:\\wwwroot\\object\\vendor\\dingo\\api\\src\\Http\\Middleware\\Request.php(103): Dingo\\Api\\Http\\Middleware\\Request->sendRequestThroughRouter(Object(Dingo\\Api\\Http\\Request))",
                "#51 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(171): Dingo\\Api\\Http\\Middleware\\Request->handle(Object(Dingo\\Api\\Http\\Request), Object(Closure))",
                "#52 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Pipeline\\Pipeline.php(105): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Illuminate\\Http\\Request))",
                "#53 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Kernel.php(145): Illuminate\\Pipeline\\Pipeline->then(Object(Closure))",
                "#54 E:\\wwwroot\\object\\vendor\\laravel\\framework\\src\\Illuminate\\Foundation\\Http\\Kernel.php(110): Illuminate\\Foundation\\Http\\Kernel->sendRequestThroughRouter(Object(Illuminate\\Http\\Request))",
                "#55 E:\\wwwroot\\object\\public\\index.php(57): Illuminate\\Foundation\\Http\\Kernel->handle(Object(Illuminate\\Http\\Request))",
                "#56 {main}"
            ]
        }
    }
}

6、虽然关联的 3 个模型已经被成功删除。如图2

图2

7、打印 $theme 对象,发现其连接已经被修改为默认的 B 数据库所对应的连接。并非模型对象中默认的 A 数据库所对应的连接。如图3

图3

8、决定在删除 $theme 对象前,重新设置其连接为 A 。最终实现如下

$theme->themeInstallation->themeInstallationVersionPreset->themeInstallationTasks()->delete();
$theme->themeInstallation->themeInstallationVersionPreset()->delete();
$theme->themeInstallation()->delete();

$theme->logs()->delete();
$theme->customPages()->delete();

$theme->setConnection('wordpress')->delete();

9、生成的删除 SQL 不再报错。分别查看 A、B 数据库中的数据,确认已被删除。如图4

图4

select * from `wp_themes` where `wp_themes`.`id` = 157 limit 1;
select * from `theme_installation` where `theme_installation`.`wp_theme_id` in (157);

select
  *
from
  `theme_installation_version_preset`
where
  `theme_installation_version_preset`.`theme_installation_id` = 47
  and `theme_installation_version_preset`.`theme_installation_id` is not null
limit
  1;

delete from
  `theme_installation_task`
where
  `theme_installation_task`.`theme_installation_version_preset_id` = 47
  and `theme_installation_task`.`theme_installation_version_preset_id` is not null;

delete from
  `theme_installation_version_preset`
where
  `theme_installation_version_preset`.`theme_installation_id` = 47
  and `theme_installation_version_preset`.`theme_installation_id` is not null;

delete from
  `theme_installation`
where
  `theme_installation`.`wp_theme_id` = 157
  and `theme_installation`.`wp_theme_id` is not null;

delete from
  `wp_themes`
where
  `id` = 157;

10、当一些关联不存在时,会报错:Trying to get property ‘themeInstallationVersionPreset’ of non-object。原因在于 $theme->themeInstallation 为 null。所以需要判断关联对象是否存在。如图5

图5

11、最终实现如下

if (isset($theme->themeInstallation)) {
 $theme->themeInstallation->themeInstallationVersionPreset->themeInstallationTasks()->delete();
 $theme->themeInstallation->themeInstallationVersionPreset()->delete();
 $theme->themeInstallation()->delete();
}

$theme->setConnection('wordpress')->delete();

12、$theme->themeInstallation 为 null 时生成的删除 SQL 不再报错。

select * from `wp_themes` where `wp_themes`.`id` = 135 limit 1;
select * from `theme_installation` where `theme_installation`.`wp_theme_id` in (135);
delete from `wp_themes` where `id` = 135;

13、$theme->themeInstallation 不为 null 时生成的删除 SQL 也不再报错。如图6

图6

select * from `wp_themes` where `wp_themes`.`id` = 143 limit 1;
select * from `theme_installation` where `theme_installation`.`wp_theme_id` in (143);

select
  *
from
  `theme_installation_version_preset`
where
  `theme_installation_version_preset`.`theme_installation_id` = 33
  and `theme_installation_version_preset`.`theme_installation_id` is not null
limit
  1;

delete from
  `theme_installation_task`
where
  `theme_installation_task`.`theme_installation_version_preset_id` = 33
  and `theme_installation_task`.`theme_installation_version_preset_id` is not null;

delete from
  `theme_installation_version_preset`
where
  `theme_installation_version_preset`.`theme_installation_id` = 33
  and `theme_installation_version_preset`.`theme_installation_id` is not null;

delete from
  `theme_installation`
where
  `theme_installation`.`wp_theme_id` = 143
  and `theme_installation`.`wp_theme_id` is not null;

delete from `wp_themes` where `id` = 143;

永夜