Question: I am new to highcharts with ruby on rails. Is there any tutorial or any idea how to fetch data from database ( SQLYog Community) and display it as chart ( Highchart) using Rails ??

Answer: 
Yes you can. You just have to return json object. You can google 'highcharts json' for more information.

Example:

[Reload chart data via JSON with Highcharts](https://stackoverflow.com/questions/4210879/reload-chart-data-via-json-with-highcharts)
I highly recommend the RailsCasts video tutorial for this.

[This is a great tutorial](http://railscasts.com/episodes/223-charts) on getting Highcharts up and running with Rails.

It will walk you through installing Highcharts and jQuery and getting your models and views set up to render charts nicely.

Once you have the basics up and running you should look through Highcharts sample code [in their demos](http://www.highcharts.com/demo/line-basic/gray).