Need Tooltips: Change google sheet existing data into DataTable

Question

Problem: All the documentation I see uses a DataTable that writes the data in the script itself. I need to call this tooltip data from existing rows. I need

Answer 1

in the embedded chart, use a data view definition to add the tooltip role...

see following snippet...

function newChart() {
  // Generate a chart representing the data in the range of A1:B15.
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getSheets()[11];

  // build the data view definition
  var COLUMN_SPEC = [
    0,
    1,
    {sourceColumn: 2, role: 'tooltip'}
  ];
  var viewSpec = Charts.newDataViewDefinition()
     .setColumns(COLUMN_SPEC)
     .build();

  var chart = sheet.newChart()
     .setChartType(Charts.ChartType.SCATTER)
     .setDataViewDefinition(viewSpec)
     .addRange(sheet.getRange('R3:S5000'))
     .addRange(sheet.getRange('Q3:Q5000'))

     .setPosition(5, 5, 0, 0)
     .build();

  sheet.insertChart(chart);
}