Overview

Google Charts is a Javascript library developed by Google to visualize data. Similar to amCharts, it has a specific way it expects the data to be provided to the API in order for the charts to work. RDS provides a way to format the results in the way Google Charts expects to receive them.

Step By Step

• In this example we will create an object that can be used with Google Charts. We will assume that we have a collection named "test" and a view named "view" with a variable named "var" that has the values 1, 2, and 3. In this example we will run a tabulation that will count the frequencies of each of these values that could be used to create a chart.

• Running the tabulation would normally look something like this:

  Tabulation

  http://{host}/rds/test/view/tabulate?dims=var

  Tabulation Output

   {
      "records": [
          [
              1,
              182
          ],
          [
              2,
              354
          ],
          [
              3,
              126
          ]
      ],
      "info": {
          "colCount": 2,
          "format": "MTNA",
          "includeMetadata": false,
          "limit": 20,
          "offset": 0,
          "moreRows": false
      }
  }

• We can add the format parameter to specify we want this to be output in a way that Google Charts expects to see it. 

  Tabulation amCharts

   http://{host}/rds/test/view/tabulate?dims=var&format=gcharts

  Tabulation amCharts Output

  {
      "cols": [
          {
              "id": "var",
              "type": "number"
          },
          {
              "id": "count",
              "type": "number"
          }
      ],
      "rows": [
          {
              "c": [
                  {
                      "v": 1
                  },
                  {
                      "v": 182
                  }
              ]
          },
          {
              "c": [
                  {
                      "v": 2
                  },
                  {
                      "v": 354
                  }
              ]
          },
          {
              "c": [
                  {
                      "v": 3
                  },
                  {
                      "v": 126
                  }
              ]
          }
      ]
  }