How to Create a Saved Report and Import Data into Google Sheets

function importCsvAppend() {
  const url = "PASTE HERE YOUR REPORT URL";
  const sheetName = "data";

  const ss = SpreadsheetApp.getActiveSpreadsheet();
  const sheet = ss.getSheetByName(sheetName) || ss.insertSheet(sheetName);

  const resp = UrlFetchApp.fetch(url, {
    muteHttpExceptions: true,
    followRedirects: true,
    headers: {
      "User-Agent": "Mozilla/5.0",
      "Accept": "text/csv,application/csv,text/plain,*/*",
    },
  });

  const code = resp.getResponseCode();
  if (code !== 200) {
    throw new Error(`CSV fetch failed: HTTP ${code}`);
  }

  const content = resp.getContentText().replace(/^\uFEFF/, "");
  const csvValues = Utilities.parseCsv(content, ";");

  if (!csvValues || csvValues.length < 2) return;

  const header = csvValues[0];
  let rows = csvValues.slice(1);

  // Write header if the sheet is empty
  if (sheet.getLastRow() === 0) {
    sheet.getRange(1, 1, 1, header.length).setValues([header]);
  }

  // Text columns (not converted to number)
  const textCols = new Set([0, 1, 2, 3, 4]);

  function parseValue(value, colIndex) {
    if (value === null || value === undefined || value === "") return "";

    const str = String(value).trim();

    // Parse date
    if (colIndex === 0 && /^\d{4}-\d{2}-\d{2}$/.test(str)) {
      const [y, m, d] = str.split("-").map(Number);
      return new Date(y, m - 1, d);
    }

    if (textCols.has(colIndex)) {
      return str;
    }

    // Parse number
    const normalized = str.replace(/\s/g, "").replace(",", ".");
    const num = Number(normalized);

    return isNaN(num) ? str : num;
  }

  rows = rows.map(r => r.map((cell, i) => parseValue(cell, i)));

  // Unique key to avoid duplicate rows
  const keyIdx = [0, 1, 2, 4];

  const lastRow = sheet.getLastRow();
  const existingKeys = new Set();

  if (lastRow >= 2) {
    const range = sheet.getRange(2, 1, lastRow - 1, Math.max(...keyIdx) + 1).getValues();

    for (const r of range) {
      const key = keyIdx.map(i => {
        const v = r[i] instanceof Date
          ? Utilities.formatDate(r[i], Session.getScriptTimeZone(), "yyyy-MM-dd")
          : String(r[i]).trim();
        return v;
      }).join("|");

      existingKeys.add(key);
    }
  }

  const newRows = [];

  for (const r of rows) {
    const key = keyIdx.map(i => {
      const v = r[i] instanceof Date
        ? Utilities.formatDate(r[i], Session.getScriptTimeZone(), "yyyy-MM-dd")
        : String(r[i]).trim();
      return v;
    }).join("|");

    if (!existingKeys.has(key)) {
      newRows.push(r);
      existingKeys.add(key);
    }
  }

  if (newRows.length) {
    const startRow = sheet.getLastRow() + 1;

    sheet.getRange(startRow, 1, newRows.length, header.length).setValues(newRows);

    // Date format
    sheet.getRange(startRow, 1, newRows.length, 1)
      .setNumberFormat("yyyy-mm-dd");

    // Number format:
    // - integers with no decimals
    // - decimals with up to 3 decimal places
    if (header.length > 5) {
      sheet.getRange(startRow, 6, newRows.length, header.length - 5)
        .setNumberFormat("#.##0,###");
    }
  }
}