With Chart.js, it is possible to create mixed charts that are a combination of two or more different chart types. A common example is a bar chart that also includes a line dataset.
Creating a mixed chart starts with the initialization of a basic chart.
At this point we have a chart rendering how we'd like. It's important to note that the default options for a line chart are not merged in this case. Only the options for the default type are merged in. In this case, that means that the default options for a bar chart are merged because that is the type specified by the `type` field.
By default, datasets are drawn so that first one is top-most. This can be altered by specifying `order` option to datasets. `order` defaults to `0`. Note that this also affects stacking, legend and tooltip. So its essentially the same as reordering the datasets.