For a pie chart, datasets need to contain an array of data points. The data points should be a number, Chart.js will total all of the numbers and calculate the relative proportion of each.
You also need to specify an array of labels so that tooltips appear correctly.
Your dataset looks nothing like the documentation.
$(function() {
var ctx = $("#myChart").get(0).getContext("2d");
var data = {
datasets: [{
data: [270, 50, 40],
backgroundColor: ["cornflowerblue", "lightgreen", "orange"],
hoverBackgroundColor: ["lightskyblue", "yellow", "darkorange"]
}],
labels: ["corn flower blue", "lightgreen", "Orange"]
};
var piechart = new Chart(ctx, {
type: 'pie',
data: data
});
});
Demo[
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