The WP-CLI command line tool is a handy application to run various WordPress tasks.
Download the WP-CLI command line tool into the WordPress root folder using CURL or WGET.
curl -O https://raw.githubusercontent.com/wp-cli/builds/gh-pages/phar/wp-cli.phar
Check if the tool is working.
php wp-cli.phar --info
Not run the search and replace command to look through all the core tables to change the URL.
php wp-cli.phar search-replace 'http://www.olddomain.com' 'http://www.newdomain.com'
This will save you numerous hours and give you some peace of mind!