Let me start RadChart is the old charting component. There is a new one (RadChartView) that resolves many of the known issues and limitations of RadChart. You can read about the differences between the controls in the RadChart vs. RadChartView
As for your question, the chart control is working with all IEnumerable collections so after fetching your data from the data base and storing it in a collection you can pass it to the chart's series ItemsSource and bind the corresponding properties from the model. You can see how to populate the chart with a collection in the Create Data-Bound Chart
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