CRITICAL: PDOException: SQLSTATE[23000]

Hi there,
When I try save a category description, the screen remains loading after it is produced a timeout errror.
 In the exception.log file show the following error:
 
[2017-07-27 15:39:10] main.CRITICAL: PDOException: SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails (`magento`.`catalog_url_rewrite_product_category`, CONSTRAINT `FK_BB79E64705D7F17FE181F23144528FC8` FOREIGN KEY (`url_rewrite_id`) REFERENCES `url_rewrite` (`url_rewrite_id`) ON DELETE CAS) in /var/www/html/vendor/magento/zendframework1/library/Zend/Db/Statement/Pdo.php:228
 
Thanks.

#0 /var/www/html/vendor/magento/zendframework1/library/Zend/Db/Statement/Pdo.php(228): PDOStatement->execute(Array)
#1 /var/www/html/vendor/magento/framework/DB/Statement/Pdo/Mysql.php(95): Zend_Db_Statement_Pdo->_execute(Array)
#2 /var/www/html/vendor/magento/zendframework1/library/Zend/Db/Statement.php(303): Magento\Framework\DB\Statement\Pdo\Mysql->_execute(Array)
#3 /var/www/html/vendor/magento/zendframework1/library/Zend/Db/Adapter/Abstract.php(480): Zend_Db_Statement->execute(Array)
#4 /var/www/html/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php(238): Zend_Db_Adapter_Abstract->query('INSERT INTO `ca...', Array)
#5 /var/www/html/vendor/magento/framework/DB/Adapter/Pdo/Mysql.php(465): Zend_Db_Adapter_Pdo_Abstract->query('INSERT INTO `ca...', Array)
#6 /var/www/html/vendor/magento/framework/DB/Adapter/Pdo/Mysql.php(520): Magento\Framework\DB\Adapter\Pdo\Mysql->_query('INSERT INTO `ca...', Array)
#7 /var/www/html/vendor/magento/framework/DB/Adapter/Pdo/Mysql.php(1939): Magento\Framework\DB\Adapter\Pdo\Mysql->query('INSERT INTO `ca...', Array)
#8 /var/www/html/vendor/magento/framework/DB/Adapter/Pdo/Mysql.php(1903): Magento\Framework\DB\Adapter\Pdo\Mysql->insertArray('catalog_url_rew...', Array, Array)
#9 /var/www/html/vendor/magento/module-catalog-url-rewrite/Model/ResourceModel/Category/Product.php(52): Magento\Framework\DB\Adapter\Pdo\Mysql->insertMultiple('catalog_url_rew...', Array)
#10 /var/www/html/vendor/magento/module-catalog-url-rewrite/Model/Category/Plugin/Storage.php(54): Magento\CatalogUrlRewrite\Model\ResourceModel\Category\Product->saveMultiple(Array)
#11 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(142): Magento\CatalogUrlRewrite\Model\Category\Plugin\Storage->aroundReplace(Object(Magento\UrlRewrite\Model\Storage\DbStorage\Interceptor), Object(Closure), Array)
#12 /var/www/html/var/generation/Magento/UrlRewrite/Model/Storage/DbStorage/Interceptor.php(39): Magento\UrlRewrite\Model\Storage\DbStorage\Interceptor->___callPlugins('replace', Array, Array)
#13 /var/www/html/vendor/magento/module-catalog-url-rewrite/Observer/CategoryProcessUrlRewriteSavingObserver.php(60): Magento\UrlRewrite\Model\Storage\DbStorage\Interceptor->replace(Array)
#14 /var/www/html/vendor/magento/framework/Event/Invoker/InvokerDefault.php(73): Magento\CatalogUrlRewrite\Observer\CategoryProcessUrlRewriteSavingObserver->execute(Object(Magento\Framework\Event\Observer))
#15 /var/www/html/vendor/magento/framework/Event/Invoker/InvokerDefault.php(61): Magento\Framework\Event\Invoker\InvokerDefault->_callObserverMethod(Object(Magento\CatalogUrlRewrite\Observer\CategoryProcessUrlRewriteSavingObserver), Object(Magento\Framework\Event\Observer))
#16 /var/www/html/vendor/magento/framework/Event/Manager.php(66): Magento\Framework\Event\Invoker\InvokerDefault->dispatch(Array, Object(Magento\Framework\Event\Observer))
#17 /var/www/html/var/generation/Magento/Framework/Event/Manager/Proxy.php(95): Magento\Framework\Event\Manager->dispatch('catalog_categor...', Array)
#18 /var/www/html/vendor/magento/framework/Model/AbstractModel.php(802): Magento\Framework\Event\Manager\Proxy->dispatch('catalog_categor...', Array)
#19 /var/www/html/vendor/magento/module-catalog/Model/Category.php(1077): Magento\Framework\Model\AbstractModel->afterSave()
#20 /var/www/html/vendor/magento/framework/EntityManager/Observer/AfterEntitySave.php(34): Magento\Catalog\Model\Category->afterSave()
#21 /var/www/html/vendor/magento/framework/Event/Invoker/InvokerDefault.php(73): Magento\Framework\EntityManager\Observer\AfterEntitySave->execute(Object(Magento\Framework\Event\Observer))
#22 /var/www/html/vendor/magento/framework/Event/Invoker/InvokerDefault.php(61): Magento\Framework\Event\Invoker\InvokerDefault->_callObserverMethod(Object(Magento\Framework\EntityManager\Observer\AfterEntitySave), Object(Magento\Framework\Event\Observer))
#23 /var/www/html/vendor/magento/framework/Event/Manager.php(66): Magento\Framework\Event\Invoker\InvokerDefault->dispatch(Array, Object(Magento\Framework\Event\Observer))
#24 /var/www/html/var/generation/Magento/Framework/Event/Manager/Proxy.php(95): Magento\Framework\Event\Manager->dispatch('magento_catalog...', Array)
#25 /var/www/html/vendor/magento/framework/EntityManager/EventManager.php(51): Magento\Framework\Event\Manager\Proxy->dispatch('magento_catalog...', Array)
#26 /var/www/html/vendor/magento/framework/EntityManager/Operation/Update.php(108): Magento\Framework\EntityManager\EventManager->dispatchEntityEvent('Magento\\Catalog...', 'save_after', Array)
#27 /var/www/html/vendor/magento/framework/EntityManager/EntityManager.php(87): Magento\Framework\EntityManager\Operation\Update->execute(Object(Magento\Catalog\Model\Category\Interceptor), Array)
#28 /var/www/html/vendor/magento/module-catalog/Model/ResourceModel/Category.php(1027): Magento\Framework\EntityManager\EntityManager->save(Object(Magento\Catalog\Model\Category\Interceptor))
#29 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(74): Magento\Catalog\Model\ResourceModel\Category->save(Object(Magento\Catalog\Model\Category\Interceptor))
#30 /var/www/html/vendor/magento/framework/Interception/Chain/Chain.php(70): Magento\Catalog\Model\ResourceModel\Category\Interceptor->___callParent('save', Array)
#31 /var/www/html/vendor/magento/framework/Interception/Chain/Chain.php(63): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Catalog...', 'save', Object(Magento\Catalog\Model\ResourceModel\Category\Interceptor), Array, 'catalogsearchFu...')
#32 /var/www/html/vendor/magento/module-catalog-search/Model/Indexer/Fulltext/Plugin/Category.php(43): Magento\Framework\Interception\Chain\Chain->Magento\Framework\Interception\Chain\{closure}(Object(Magento\Catalog\Model\Category\Interceptor))
#33 /var/www/html/vendor/magento/module-catalog-search/Model/Indexer/Fulltext/Plugin/Category.php(29): Magento\CatalogSearch\Model\Indexer\Fulltext\Plugin\Category->addCommitCallback(Object(Magento\Catalog\Model\ResourceModel\Category\Interceptor), Object(Closure), Object(Magento\Catalog\Model\Category\Interceptor))
#34 /var/www/html/vendor/magento/framework/Interception/Chain/Chain.php(67): Magento\CatalogSearch\Model\Indexer\Fulltext\Plugin\Category->aroundSave(Object(Magento\Catalog\Model\ResourceModel\Category\Interceptor), Object(Closure), Object(Magento\Catalog\Model\Category\Interceptor))
#35 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(138): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Catalog...', 'save', Object(Magento\Catalog\Model\ResourceModel\Category\Interceptor), Array, 'clean_cache')
#36 /var/www/html/vendor/magento/framework/App/Cache/FlushCacheByTags.php(71): Magento\Catalog\Model\ResourceModel\Category\Interceptor->Magento\Framework\Interception\{closure}(Object(Magento\Catalog\Model\Category\Interceptor))
#37 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(142): Magento\Framework\App\Cache\FlushCacheByTags->aroundSave(Object(Magento\Catalog\Model\ResourceModel\Category\Interceptor), Object(Closure), Object(Magento\Catalog\Model\Category\Interceptor))
#38 /var/www/html/var/generation/Magento/Catalog/Model/ResourceModel/Category/Interceptor.php(52): Magento\Catalog\Model\ResourceModel\Category\Interceptor->___callPlugins('save', Array, Array)
#39 /var/www/html/vendor/magento/framework/Model/AbstractModel.php(631): Magento\Catalog\Model\ResourceModel\Category\Interceptor->save(Object(Magento\Catalog\Model\Category\Interceptor))
#40 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(146): Magento\Framework\Model\AbstractModel->save()
#41 /var/www/html/var/generation/Magento/Catalog/Model/Category/Interceptor.php(26): Magento\Catalog\Model\Category\Interceptor->___callPlugins('save', Array, Array)
#42 /var/www/html/vendor/magento/module-catalog/Controller/Adminhtml/Category/Save.php(203): Magento\Catalog\Model\Category\Interceptor->save()
#43 /var/www/html/vendor/magento/framework/App/Action/Action.php(102): Magento\Catalog\Controller\Adminhtml\Category\Save->execute()
#44 /var/www/html/vendor/magento/module-backend/App/AbstractAction.php(226): Magento\Framework\App\Action\Action->dispatch(Object(Magento\Framework\App\Request\Http))
#45 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(74): Magento\Backend\App\AbstractAction->dispatch(Object(Magento\Framework\App\Request\Http))
#46 /var/www/html/vendor/magento/framework/Interception/Chain/Chain.php(70): Magento\Catalog\Controller\Adminhtml\Category\Save\Interceptor->___callParent('dispatch', Array)
#47 /var/www/html/vendor/magento/framework/Interception/Chain/Chain.php(63): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Catalog...', 'dispatch', Object(Magento\Catalog\Controller\Adminhtml\Category\Save\Interceptor), Array, 'adminAuthentica...')
#48 /var/www/html/vendor/magento/module-backend/App/Action/Plugin/Authentication.php(143): Magento\Framework\Interception\Chain\Chain->Magento\Framework\Interception\Chain\{closure}(Object(Magento\Framework\App\Request\Http))
#49 /var/www/html/vendor/magento/framework/Interception/Chain/Chain.php(67): Magento\Backend\App\Action\Plugin\Authentication->aroundDispatch(Object(Magento\Catalog\Controller\Adminhtml\Category\Save\Interceptor), Object(Closure), Object(Magento\Framework\App\Request\Http))
#50 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(138): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Catalog...', 'dispatch', Object(Magento\Catalog\Controller\Adminhtml\Category\Save\Interceptor), Array, 'adminMassaction...')
#51 /var/www/html/vendor/magento/module-backend/App/Action/Plugin/MassactionKey.php(33): Magento\Catalog\Controller\Adminhtml\Category\Save\Interceptor->Magento\Framework\Interception\{closure}(Object(Magento\Framework\App\Request\Http))
#52 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(142): Magento\Backend\App\Action\Plugin\MassactionKey->aroundDispatch(Object(Magento\Catalog\Controller\Adminhtml\Category\Save\Interceptor), Object(Closure), Object(Magento\Framework\App\Request\Http))
#53 /var/www/html/var/generation/Magento/Catalog/Controller/Adminhtml/Category/Save/Interceptor.php(26): Magento\Catalog\Controller\Adminhtml\Category\Save\Interceptor->___callPlugins('dispatch', Array, Array)
#54 /var/www/html/vendor/magento/framework/App/FrontController.php(55): Magento\Catalog\Controller\Adminhtml\Category\Save\Interceptor->dispatch(Object(Magento\Framework\App\Request\Http))
#55 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(74): Magento\Framework\App\FrontController->dispatch(Object(Magento\Framework\App\Request\Http))
#56 /var/www/html/vendor/magento/framework/Interception/Chain/Chain.php(70): Magento\Framework\App\FrontController\Interceptor->___callParent('dispatch', Array)
#57 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(138): Magento\Framework\Interception\Chain\Chain->invokeNext('Magento\\Framewo...', 'dispatch', Object(Magento\Framework\App\FrontController\Interceptor), Array, 'install')
#58 /var/www/html/vendor/magento/framework/Module/Plugin/DbStatusValidator.php(69): Magento\Framework\App\FrontController\Interceptor->Magento\Framework\Interception\{closure}(Object(Magento\Framework\App\Request\Http))
#59 /var/www/html/vendor/magento/framework/Interception/Interceptor.php(142): Magento\Framework\Module\Plugin\DbStatusValidator->aroundDispatch(Object(Magento\Framework\App\FrontController\Interceptor), Object(Closure), Object(Magento\Framework\App\Request\Http))
#60 /var/www/html/var/generation/Magento/Framework/App/FrontController/Interceptor.php(26): Magento\Framework\App\FrontController\Interceptor->___callPlugins('dispatch', Array, Array)
#61 /var/www/html/vendor/magento/framework/App/Http.php(135): Magento\Framework\App\FrontController\Interceptor->dispatch(Object(Magento\Framework\App\Request\Http))
#62 /var/www/html/vendor/magento/framework/App/Bootstrap.php(258): Magento\Framework\App\Http->launch()
#63 /var/www/html/index.php(39): Magento\Framework\App\Bootstrap->run(Object(Magento\Framework\App\Http))
#64 {main}