使用数据库数据在Google图表上显示报告

Question

I am very new to reporting and mvc. Im trying to get my database data to populate my reports. The reports i have so far are hard coded but i have tried to use a raw query function which got from Return count using raw query, using Entity Framework and MVC to assist me. However i am still struggling to get the chart to display the database data.

report view:

<script type="text/javascript" src="https://www.google.com/jsapi"></script>
<script type="text/javascript">
    google.load("visualization", "1", { packages: ["corechart"] });
    google.setOnLoadCallback(drawChart);

    var sql = "SELECT COUNT(*) FROM dbo.School WHERE (SchoolName = Accountancy)";
    var total = _context.Database.SqlQuery < int > (sql).single();

    function drawChart() {                                
        var data = google.visualization.arrayToDataTable([
                       ['Task', 'Hours per Day'],
                       ['Accountancy', total],
                       ['Economics and Business', 2],
                       ['Law', 2],
                       ['Governance', 2],
                       ['Business', 7]
                   ]);

        var options = {
                          title: 'Sample (Until we figure out how to get database data)'
                      };

        var chart = new google.visualization.PieChart(document.getElementById('piechart'));

        chart.draw(data, options);
    }
</script>

<div id="piechart" style="width:800px; height: 600px;"></div>
</div>

I tried to get the "Accounting" field to display but the chart didn't display the accounting total, it only displays the totals for the others (which are hard-coded)

Is there anything specific that needs to be coded to get this data ie like in the controller?.. just to remind I am very new to this

Answer 1

The question you're referencing is showing C# code. I know this can be confusing with the use of var (I'm not a big fan of var in C#). I'm not sure what the MVC 3 way of doing this would be, but you can't mix client and server-side code directly. In later versions of MVC, I think you can use Razor syntax to bind the server-side query result to your client-side javascript code.

An additional piece of advice: Take baby steps. You're jumping into a lot of concepts all at once if you've never done anything like this. You need to learn SQL, Entity Framework, Asp.net-mvc, Javascript, and the Google Charts API all at once to pull this off.

First try just to display the number on the page before trying to display a complicated interactive chart. For that matter, before you can do that you need to learn how to pull data from SQL into memory on your server.