Hi Alex,

Data sources can be accessed directly in JavaScript, allowing you to set the value of any component based on the data source. The steps below should help you set started.

Navigate to the data sources screen and click the \"Data Source Id\" menu option. This will reveal a dialogue showing the id of the data source along with some example code.
Open the form builder screen and drag-n-drop a number field (or text field) into your form. Since days are typically a number, I think a number field make more sense.

In the calculated value enter the following JavaScript. You will need to modify the JavaScript to match your specific data source ids, field names and column names.

async function calculateLeave(){\n    const dataSoruceRows =  await tf.getDataSource('enter your data source id here')\n    const totalHours = _(dataSoruceRows)\n        .filter(row => row?.leaveType === 'sickLeave')\n        .sumBy('daysRequested')\n    return totalHours\n}\n\nvalue = calculateLeave()

You should find that the total of the data source will appear in the number field / text field.

reference a data source in a text field