Scenario:
Old Site: www.domain.com/blog
Path: /home/domain/public_html/blog
New Site: www.domain.com (Assume the site is empty)
Path: /home/domain/public_html
In order to move the WordPress account manually without any plugin, you may done it through SSH without any trouble.
Folder/File
1. Log into the SSH.
2. Copy the folder and file from blog folder to main site.
cp -apr /home/domain/public_html/blog /home/domain/public_html
3. If you using Permalink and having mod_rewrite rule, you may edit your .htaccess file,
vi /home/domain/public_html/.htaccess
4. Change the rewrite rule from,
RewriteEngine On
RewriteBase /blog/
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /blog/index.php [L]
to
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
Database:
1. Dump the database. Assume your database named wordpress.
mysqldump wordpress > wordpress.sql
2. Change the entry from www.domain.com/blog to www.domain.com.
sed -i 's/www\.domain.\com\/blog/www\.domain\.com/g' wordpress.sql
3. Restore the database back to the domain.
mysql wordpress < wordpress.sql