Error with auto creat table

I am a student and studying about CentOS. I installed and configured ELGG to use with NGINX. I would like to ask for help with this error:

*3 FastCGI sent in stderr: "PHP message: Exception #1425288709 : fatal error in exception handler : Table 'elggdb.elgg_config' doesn't exist

If I understand it right, after configured, all the tables should be created automatically, and I got this error in the log file instead. Here are my configuration details:

ELGG was installed in /var/www/sampleweb/elgg/

settings.php

$CONFIG->dbuser = 'elgguser';

$CONFIG->dbpass = '123456';

$CONFIG->dbname = 'elggdb';

$CONFIG->dbhost = 'localhost';

$CONFIG->dbprefix = 'elgg_';

 

php.ini

mysql.default_host = "localhost"

mysql.default_user = "root"

mysql.default_password = "123456"

 

My configuration file of Nginx (default from ELGG sample)

server {
    listen 80;
    server_name elgg.hieudang.test;

    # Server root, replace it with your elgg installation location
    root /var/www/sampleweb/elgg/;
    index index.php index.html index.htm;

... }

I also granted all privileges to elgguser@localhost indentified by '123456' in MySQL. With this error, I am not sure if i made a mistake when installing ELGG or it was from MySQL. Any help is appreciated!