每次第一次登陆后台的时候提示“系统错误 请检查错误日志”

每次第一次登陆后台的时候提示“系统错误 请检查错误日志”，多次点击登陆后，就会登陆成功，查看错误日志显示连接数据库时出错。如下：（什么原因呢）

<?php defined('SYSTEMPATH') || exit('No direct script access allowed'); ?>

ERROR - 2020-10-17 08:08:04 --> Error connecting to the database: ����Ŀ�����������ܾ����޷����ӡ�

CRITICAL - 2020-10-17 08:08:04 --> Unable to connect to the database.

#SQL：

#URL：http://www.jieke248.com/admin.php?c=login&m=index&go=http://www.jieke248.com/admin.php

#REFERER：http://www.jieke248.com/admin.php?c=login&m=index&go=http://www.jieke248.com/admin.php

#0 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Database\BaseConnection.php(646): CodeIgniter\Database\BaseConnection->initialize()

#1 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Database\BaseBuilder.php(1860): CodeIgniter\Database\BaseConnection->query('SELECT `passwor...', Array, false)

#2 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\Fcms\Model\Auth.php(123): CodeIgniter\Database\BaseBuilder->get()

#3 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\Core\Controllers\Admin\Login.php(38): Phpcmf\Model\Auth->login('admin', 'admin')

#4 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\CodeIgniter.php(918): Phpcmf\Controllers\Admin\Login->index()

#5 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\CodeIgniter.php(404): CodeIgniter\CodeIgniter->runController(Object(Phpcmf\Controllers\Admin\Login))

#6 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\CodeIgniter.php(312): CodeIgniter\CodeIgniter->handleRequest(NULL, Object(Config\Cache), false)

#7 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\Fcms\Init.php(378): CodeIgniter\CodeIgniter->run()

#8 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\index.php(47): require('E:\\TOOL\\PhpStud...')

#9 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\admin.php(9): require('E:\\TOOL\\PhpStud...')

#10 {main}

CRITICAL - 2020-10-17 08:09:09 --> Argument 2 passed to CodeIgniter\Debug\Toolbar::renderTimeline() must be of the type float, null given, called in E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Debug\Toolbar\Views\toolbar.tpl.php on line 128

#SQL：

#URL：http://www.jieke248.com/admin.php?debugbar_time=1602893349

#REFERER：http://www.jieke248.com/admin.php?c=error&m=index

#0 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Debug\Toolbar\Views\toolbar.tpl.php(128): CodeIgniter\Debug\Toolbar->renderTimeline(Array, NULL, NULL, NULL, Array)

#1 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Debug\Toolbar.php(498): include('E:\\TOOL\\PhpStud...')

#2 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Debug\Toolbar.php(455): CodeIgniter\Debug\Toolbar->format(Array, 'html')

#3 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\Fcms\Core\Hooks.php(57): CodeIgniter\Debug\Toolbar->respond()

#4 [internal function]: Phpcmf\Hooks::Phpcmf\{closure}()

#5 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Events\Events.php(188): call_user_func(Object(Closure))

#6 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\CodeIgniter.php(293): CodeIgniter\Events\Events::trigger('pre_system')

#7 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\Fcms\Init.php(378): CodeIgniter\CodeIgniter->run()

#8 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\index.php(47): require('E:\\TOOL\\PhpStud...')

#9 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\admin.php(9): require('E:\\TOOL\\PhpStud...')

#10 {main}

CRITICAL - 2020-10-17 08:09:42 --> Argument 2 passed to CodeIgniter\Debug\Toolbar::renderTimeline() must be of the type float, null given, called in E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Debug\Toolbar\Views\toolbar.tpl.php on line 128

#SQL：

#URL：http://www.jieke248.com/admin.php?debugbar_time=1602893381

#REFERER：http://www.jieke248.com/admin.php?c=error&m=index

#0 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Debug\Toolbar\Views\toolbar.tpl.php(128): CodeIgniter\Debug\Toolbar->renderTimeline(Array, NULL, NULL, NULL, Array)

#1 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Debug\Toolbar.php(498): include('E:\\TOOL\\PhpStud...')

#2 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Debug\Toolbar.php(455): CodeIgniter\Debug\Toolbar->format(Array, 'html')

#3 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\Fcms\Core\Hooks.php(57): CodeIgniter\Debug\Toolbar->respond()

#4 [internal function]: Phpcmf\Hooks::Phpcmf\{closure}()

#5 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\Events\Events.php(188): call_user_func(Object(Closure))

#6 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\System\CodeIgniter.php(293): CodeIgniter\Events\Events::trigger('pre_system')

#7 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\dayrui\Fcms\Init.php(378): CodeIgniter\CodeIgniter->run()

#8 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\index.php(47): require('E:\\TOOL\\PhpStud...')

#9 E:\TOOL\PhpStudy20180211\PHPTutorial\WWW\jieke248\admin.php(9): require('E:\\TOOL\\PhpStud...')

#10 {main}