gfolder Copy in eojji.kr, https://file.eojji.kr/copy

If sheet is greater than 30,000.gs

  if (sheetFiles.getLastRow() > 30000) {
    var parentId = sheetFolder.getRange('C3').getValue(); // Copy to folder, id2
    var title = copyFolderSs.getName()+'_backup';
    // https://developers.google.com/drive/v2/reference/files/copy
    var respCopy = copyDriveFile_(title, ssId, parentId);    
    if (respCopy && respCopy.id) {
      rowContents = ['gfolder 스프레드시트 파일 복사', '=HYPERLINK("'+respCopy.alternateLink+'","'+title+'")'];  
      logSheetAppendRow(logSpreadSheet, rowContents);  
      
      // delete: start ~ filesRow - 2
      var startRow = 3;
      var filesRow = sheetFiles.getRange('B1').getValue();  
      var howMany = filesRow - startRow - 1; 
      sheetFiles.deleteRows(startRow, howMany);   
      sheetFiles.getRange('B1').setValue(filesRow - howMany); 
    }
  }