I got many error messages from my installation:

[error] 13191#13191: *1102 FastCGI sent in stderr: "PHP message: Error in Piwik: Invalid MySQL Version" while reading response header from upstream, client: *****, server: localhost, request: "GET /index.php?module=Marketplace&action=getPremiumFeatures&widget=undefined&idSite=1&period=day&date=today&showtitle=1&random=239 HTTP/1.1"

Piwik version: 3.0.4

I installed piwik on Azure cloud service, using MySQL on Azure service, MySQL version: 5.7

system: ubuntu 16.04 LTS
php: PHP Version 7.0.22-0ubuntu0.16.04.1
php-mysql: Client API library version | mysqlnd 5.0.12-dev - 20150407