First, the number of MySQL databases available at the MySQL web hosting plan should be enough for your needs. Each script or web application should have its own MySQL databases, so make sure the MySQL web hosting provider can offer enough MySQL databases for your websites. Some MySQL web hosting offer unlimited MySQL databases which more flexible for webmasters.
MySQL web hosting control Interface is also important. MySQL web hosting provider should have an interface which is easy to use and if you have many staff involved in the building of various tables and databases, you should be able to create multiple user IDs to allow different degrees of secure access.
MySQL web hosting is better to have cron job support. A cron job helps you to run specific scripts automatically on a regular basis. A MySQL hosting provider should allow you to manage the cron job at your control panel easily. *
MySQL web hosting should also provide specific support for MySQL databases. MySQL web hosting provider should have trained support staff with deep knowledgeable in MySQL database management.
Below are the best MySQL Web Hosting companies on the internet tried and true.
JustHost Is Best MySQL Web Hosting

* UNLIMITED Hosting Space
* Unlimited bandwidth transfer
* hostmonster 24/7 Superb/Responsive Sales/Support
* Unlimited POP/Imap Email Accounts
* Free domain name
* SSH (Secure Shell), SSL, FTP, Stats
* CGI, Ruby (RoR), Perl, PHP, MySQL
* 12 months : $3.45/mo
** This Justhost Review is hosted with Justhost Hosting.

hostmonster Is Best MySQL Web Hosting

* UNLIMITED Hosting Space
* Unlimited bandwidth transfer
* hostmonster 24/7 Superb/Responsive Sales/Support
* 2,500 POP/Imap Email Accounts
* Free domain name
* SSH (Secure Shell), SSL, FTP, Stats
* CGI, Ruby (RoR), Perl, PHP, MySQL
* 12 months : $5.95/mo
** This Hostmonster Review is hosted with Hostmonster Hosting.
Bluehost Is Best MySQL Web Hosting

* UNLIMITED Hosting Space
* Unlimited bandwidth transfer
* Bluehost 24/7 Superb/Responsive Sales/Support
* 2,500 POP/Imap Email Accounts
* Free domain name
* SSH (Secure Shell), SSL, FTP, Stats
* CGI, Ruby (RoR), Perl, PHP, MySQL
* 24 months : $6.95/mo
* 12 months : $7.95/mo
** This Bluehost Review is hosted with Bluehost Hosting.

hostgator Is Best MySQL Web Hosting

* UNLIMITED Hosting Space
* Unlimited bandwidth transfer
* HostGator 24/7 Superb/Responsive Sales/Support
* Unlimited POP/Imap Email Accounts
* Free domain name
* SSH (Secure Shell), SSL, FTP, Stats
* CGI, Ruby (RoR), Perl, PHP, MySQL
* 12 months : $7.95/mo
** This HostGator Review is hosted with HostGator Hosting.