Magento – An error has happened during application run. See exception log for details

I install magento 2.1.2 on localhost. Try to open it then it gives this error.

An error has happened during application run. See exception log for details.

If i use developer mode to see the message.
(To Use Developer Mode : In .htaccess file i Comment out "SetEnv MAGE_MODE developer")

Then It shows This message

exception 'PDOException' with message 'SQLSTATE[HY000] [1049] Unknown database 'magento2'' in G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Pdo\Abstract.php:129 Stack trace: #0 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Pdo\Abstract.php(129): PDO->__construct('mysql:host=loca…', 'root', '', Array) #1 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Pdo\Mysql.php(111): Zend_Db_Adapter_Pdo_Abstract->_connect() #2 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\DB\Adapter\Pdo\Mysql.php(347): Zend_Db_Adapter_Pdo_Mysql->_connect() #3 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Abstract.php(861): Magento\Framework\DB\Adapter\Pdo\Mysql->_connect() #4 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Abstract.php(931): Zend_Db_Adapter_Abstract->quote('default', NULL) #5 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\DB\Adapter\Pdo\Mysql.php(1372): Zend_Db_Adapter_Abstract->quoteInto('{{fieldName}} =…', 'default', NULL, NULL) #6 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\DB\Adapter\Pdo\Mysql.php(2830): Magento\Framework\DB\Adapter\Pdo\Mysql->quoteInto('{{fieldName}} =…', 'default') #7 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\DB\Adapter\Pdo\Mysql.php(2814): Magento\Framework\DB\Adapter\Pdo\Mysql->_prepareQuotedSqlCondition('{{fieldName}} =…', 'default', 'scope') #8 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Data\Collection\AbstractDb.php(477): Magento\Framework\DB\Adapter\Pdo\Mysql->prepareSqlCondition('scope', 'default') #9 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Data\Collection\AbstractDb.php(408): Magento\Framework\Data\Collection\AbstractDb->_getConditionSql('scope', 'default') #10 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Data\Collection\AbstractDb.php(390): Magento\Framework\Data\Collection\AbstractDb->_translateCondition('scope', 'default') #11 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\module-store\Model\ResourceModel\Config\Collection\Scoped.php(59): Magento\Framework\Data\Collection\AbstractDb->addFieldToFilter('scope', 'default') #12 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Model\ResourceModel\Db\Collection\AbstractCollection.php(124): Magento\Store\Model\ResourceModel\Config\Collection\Scoped->_initSelect() #13 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\module-store\Model\ResourceModel\Config\Collection\Scoped.php(48): Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection->__construct(Object(Magento\Framework\Data\Collection\EntityFactory), Object(Magento\Framework\Logger\Monolog), Object(Magento\Framework\Data\Collection\Db\FetchStrategy\Query), Object(Magento\Framework\Event\Manager\Proxy), NULL, Object(Magento\Config\Model\ResourceModel\Config\Data)) #14 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\ObjectManager\Factory\AbstractFactory.php(93): Magento\Store\Model\ResourceModel\Config\Collection\Scoped->__construct(Object(Magento\Framework\Data\Collection\EntityFactory), Object(Magento\Framework\Logger\Monolog), Object(Magento\Framework\Data\Collection\Db\FetchStrategy\Query), Object(Magento\Framework\Event\Manager\Proxy), Object(Magento\Config\Model\ResourceModel\Config\Data), 'default', NULL, NULL) #15 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\ObjectManager\Factory\Dynamic\Developer.php(89): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject('Magento\Store\M…', Array) #16 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\ObjectManager\ObjectManager.php(57): Magento\Framework\ObjectManager\Factory\Dynamic\Developer->create('Magento\Store\M…', Array) #17 G:\Xxamp\htdocs\magento2.1.2\var\generation\Magento\Store\Model\ResourceModel\Config\Collection\ScopedFactory.php(43): Magento\Framework\ObjectManager\ObjectManager->create('\Magento\Store\…', Array) #18 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\module-store\Model\Config\Reader\DefaultReader.php(63): Magento\Store\Model\ResourceModel\Config\Collection\ScopedFactory->create(Array) #19 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Config\ScopePool.php(112): Magento\Store\Model\Config\Reader\DefaultReader->read() #20 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Config.php(45): Magento\Framework\App\Config\ScopePool->getScope('default', NULL) #21 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Config.php(58): Magento\Framework\App\Config->getValue('web/secure/use_…', 'default', NULL) #22 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\module-store\Model\HeaderProvider\Hsts.php(48): Magento\Framework\App\Config->isSetFlag('web/secure/use_…') #23 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Response\HeaderManager.php(41): Magento\Store\Model\HeaderProvider\Hsts->canApply() #24 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Interception\Interceptor.php(123): Magento\Framework\App\Response\HeaderManager->beforeSendResponse(Object(Magento\Framework\App\Response\Http\Interceptor)) #25 G:\Xxamp\htdocs\magento2.1.2\var\generation\Magento\Framework\App\Response\Http\Interceptor.php(117): Magento\Framework\App\Response\Http\Interceptor->___callPlugins('sendResponse', Array, Array) #26 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Http.php(185): Magento\Framework\App\Response\Http\Interceptor->sendResponse() #27 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Http.php(156): Magento\Framework\App\Http->handleDeveloperMode(Object(Magento\Framework\App\Bootstrap), Object(Zend_Db_Adapter_Exception)) #28 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Bootstrap.php(263): Magento\Framework\App\Http->catchException(Object(Magento\Framework\App\Bootstrap), Object(Zend_Db_Adapter_Exception)) #29 G:\Xxamp\htdocs\magento2.1.2\index.php(39): Magento\Framework\App\Bootstrap->run(Object(Magento\Framework\App\Http)) #30 {main} Next exception 'Zend_Db_Adapter_Exception' with message 'SQLSTATE[HY000] [1049] Unknown database 'magento2'' in G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Pdo\Abstract.php:144 Stack trace: #0 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Pdo\Mysql.php(111): Zend_Db_Adapter_Pdo_Abstract->_connect() #1 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\DB\Adapter\Pdo\Mysql.php(347): Zend_Db_Adapter_Pdo_Mysql->_connect() #2 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Abstract.php(861): Magento\Framework\DB\Adapter\Pdo\Mysql->_connect() #3 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\zendframework1\library\Zend\Db\Adapter\Abstract.php(931): Zend_Db_Adapter_Abstract->quote('default', NULL) #4 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\DB\Adapter\Pdo\Mysql.php(1372): Zend_Db_Adapter_Abstract->quoteInto('{{fieldName}} =…', 'default', NULL, NULL) #5 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\DB\Adapter\Pdo\Mysql.php(2830): Magento\Framework\DB\Adapter\Pdo\Mysql->quoteInto('{{fieldName}} =…', 'default') #6 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\DB\Adapter\Pdo\Mysql.php(2814): Magento\Framework\DB\Adapter\Pdo\Mysql->_prepareQuotedSqlCondition('{{fieldName}} =…', 'default', 'scope') #7 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Data\Collection\AbstractDb.php(477): Magento\Framework\DB\Adapter\Pdo\Mysql->prepareSqlCondition('scope', 'default') #8 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Data\Collection\AbstractDb.php(408): Magento\Framework\Data\Collection\AbstractDb->_getConditionSql('scope', 'default') #9 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Data\Collection\AbstractDb.php(390): Magento\Framework\Data\Collection\AbstractDb->_translateCondition('scope', 'default') #10 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\module-store\Model\ResourceModel\Config\Collection\Scoped.php(59): Magento\Framework\Data\Collection\AbstractDb->addFieldToFilter('scope', 'default') #11 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Model\ResourceModel\Db\Collection\AbstractCollection.php(124): Magento\Store\Model\ResourceModel\Config\Collection\Scoped->_initSelect() #12 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\module-store\Model\ResourceModel\Config\Collection\Scoped.php(48): Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection->__construct(Object(Magento\Framework\Data\Collection\EntityFactory), Object(Magento\Framework\Logger\Monolog), Object(Magento\Framework\Data\Collection\Db\FetchStrategy\Query), Object(Magento\Framework\Event\Manager\Proxy), NULL, Object(Magento\Config\Model\ResourceModel\Config\Data)) #13 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\ObjectManager\Factory\AbstractFactory.php(93): Magento\Store\Model\ResourceModel\Config\Collection\Scoped->__construct(Object(Magento\Framework\Data\Collection\EntityFactory), Object(Magento\Framework\Logger\Monolog), Object(Magento\Framework\Data\Collection\Db\FetchStrategy\Query), Object(Magento\Framework\Event\Manager\Proxy), Object(Magento\Config\Model\ResourceModel\Config\Data), 'default', NULL, NULL) #14 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\ObjectManager\Factory\Dynamic\Developer.php(89): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject('Magento\Store\M…', Array) #15 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\ObjectManager\ObjectManager.php(57): Magento\Framework\ObjectManager\Factory\Dynamic\Developer->create('Magento\Store\M…', Array) #16 G:\Xxamp\htdocs\magento2.1.2\var\generation\Magento\Store\Model\ResourceModel\Config\Collection\ScopedFactory.php(43): Magento\Framework\ObjectManager\ObjectManager->create('\Magento\Store\…', Array) #17 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\module-store\Model\Config\Reader\DefaultReader.php(63): Magento\Store\Model\ResourceModel\Config\Collection\ScopedFactory->create(Array) #18 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Config\ScopePool.php(112): Magento\Store\Model\Config\Reader\DefaultReader->read() #19 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Config.php(45): Magento\Framework\App\Config\ScopePool->getScope('default', NULL) #20 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Config.php(58): Magento\Framework\App\Config->getValue('web/secure/use_…', 'default', NULL) #21 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\module-store\Model\HeaderProvider\Hsts.php(48): Magento\Framework\App\Config->isSetFlag('web/secure/use_…') #22 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Response\HeaderManager.php(41): Magento\Store\Model\HeaderProvider\Hsts->canApply() #23 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\Interception\Interceptor.php(123): Magento\Framework\App\Response\HeaderManager->beforeSendResponse(Object(Magento\Framework\App\Response\Http\Interceptor)) #24 G:\Xxamp\htdocs\magento2.1.2\var\generation\Magento\Framework\App\Response\Http\Interceptor.php(117): Magento\Framework\App\Response\Http\Interceptor->___callPlugins('sendResponse', Array, Array) #25 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Http.php(185): Magento\Framework\App\Response\Http\Interceptor->sendResponse() #26 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Http.php(156): Magento\Framework\App\Http->handleDeveloperMode(Object(Magento\Framework\App\Bootstrap), Object(Zend_Db_Adapter_Exception)) #27 G:\Xxamp\htdocs\magento2.1.2\vendor\magento\framework\App\Bootstrap.php(263): Magento\Framework\App\Http->catchException(Object(Magento\Framework\App\Bootstrap), Object(Zend_Db_Adapter_Exception)) #28 G:\Xxamp\htdocs\magento2.1.2\index.php(39): Magento\Framework\App\Bootstrap->run(Object(Magento\Framework\App\Http)) #29 {main}

What is the Solution For this Problem .. Can anyone guide me .