How to remove duplicate rows of csv file using nodejs

This solution is inefficient, I believe it's O(n^2), but it will work, if we assume that your CSV is represented in javascript as a 2D array of strings (i.e. string[][] in typescript notation).

const table = loadCsv(...); // this line is pseudocode

/**
 * Check if two arrays are the same
 */
function rowCompare(rowA, rowB) {
  if (rowA.length !== rowB.length) return false;
  for (let i = 0; i < rowA.length; i++) {
    if (rowA[i] !== rowB[i]) return false;
  }
  return true;
}

const dedupedTable = table.filter((row, ind, arr) => {
  return ind === arr.findIndex(r => rowCompare(row, r))
});

The dedupedTable variable should now contain your table, with any duplicate rows removed.