sum a values in a column

I am not really sure what you are looking for. But to calculate the sum of all values of a field in a list of records have a look at this code snippet:

a!localVariables(
  local!test1: {
    {
      item: "stapler",
      name: "Mike",
      countryId: 1
    },
    {
      item: "printer",
      name: "Larrys",
      countryId: 2
    },
    {
      item: "printer",
      name: "Larry",
      countryId: 2
    },
    {
      item: "laptop",
      name: "Mike",
      countryId: 1
    },
    {
      item: "glass",
      name: "Mike",
      countryId: 3
    }
  },


  sum(local!test1.countryId)
)

You can query the data for the column from the database and then you use the sum() for addition.

In the above, for a Order Line Item record, the data is queried for a column and then addition has been done

Thank you

This is working