[Chartjs]-How can I sort, insert in between and update full dataset in chartjs?

There is no option built in, but it is pretty easy to write your own using the addData, removeData methods that Chart.js provides.

var MyBarChartMethods = {
    // sort a dataset
    sort: function (chart, datasetIndex) {
        var data = []
        chart.datasets.forEach(function (dataset, i) {
            dataset.bars.forEach(function (bar, j) {
                if (i === 0) {
                    data.push({
                        label: chart.scale.xLabels[j],
                        values: [bar.value]
                    })
                } else 
                    data[j].values.push(bar.value)
            });
        })

        data.sort(function (a, b) {
            if (a.values[datasetIndex] > b.values[datasetIndex])
                return -1;
            else if (a.values[datasetIndex] < b.values[datasetIndex])
                return 1;
            else
                return 0;
        })

        chart.datasets.forEach(function (dataset, i) {
            dataset.bars.forEach(function (bar, j) {
                if (i === 0)
                    chart.scale.xLabels[j] = data[j].label;
                bar.label = data[j].label;
                bar.value = data[j].values[i];
            })
        });
        chart.update();
    },
    // reload data
    reload: function (chart, datasetIndex, labels, values) {
        var diff = chart.datasets[datasetIndex].bars.length - values.length;
        if (diff < 0) {
            for (var i = 0; i < -diff; i++)
                chart.addData([0], "");
        } else if (diff > 0) {
            for (var i = 0; i < diff; i++)
                chart.removeData();
        }

        chart.datasets[datasetIndex].bars.forEach(function (bar, i) {
            chart.scale.xLabels[i] = labels[i];
            bar.value = values[i];
        })
        chart.update();
    }
}

which you call like so (where myBarChart is your chart)

// sort
MyBarChartMethods.sort(myBarChart, 0)
// reload - same number of values
MyBarChartMethods.reload(myBarChart, 0, ["J", "F", "M", "A", "M", "J", "J"], [1, 2, 3, 4, 5, 6, 7])
// reload - more values
MyBarChartMethods.reload(myBarChart, 0, ["J", "F", "M", "A", "M", "J", "J", "A"], [1, 2, 3, 4, 5, 6, 7, 8])
// reload - less values
MyBarChartMethods.reload(myBarChart, 0, ["J", "F", "M", "A", "M"], [1, 2, 3, 4, 5])

Inserting 2 points is special case of reload, so you can use the same function (or write your own based on that easily)

Fiddle – http://jsfiddle.net/Lkdxxkfa/