A Google Apps Script for generating automated time stamping in Google Sheets

SheetTimeStamper.gs

/*/////////////////////////////////////////////////////////////////////////

SHEET TIME STAMPER - (FOR USE IN GOOGLE SHEETS)

The initial configuration generates a unique time stamp on the line of 
of the specified sheet ("Sheet1") whenever the corresponding cell in 
column 4 is NOT empty. Included is an additional configuration which will
perform this same action on multiple columns simultaneously.

###############################
### "think outside the box" ###
###   ($) ¯\_(ツ)_/¯ (฿)    ###
###############################

/////////////////////////////////////////////////////////////////////////*/

function onEdit() {
  var s = SpreadsheetApp.getActiveSheet();
  if( s.getName() == "Sheet1" ) { //checks that we're on the correct sheet
    var r = s.getActiveCell();
    if( r.getColumn() == 4 ) { //checks the column
      var nextCell = r.offset(0, 1);
      if( nextCell.getValue() === '' ) //is empty?
        nextCell.setValue(new Date());
    }
  }
}

/*/////////////////////////////////////////////////////////////////////////

function onEdit() {
var s = SpreadsheetApp.getActiveSheet();
if( s.getName() == "Sheet1" ) { //checks that we're on the correct sheet
var r = s.getActiveCell();
if( r.getColumn() == 5 ) { //checks the column
var nextCell = r.offset(0, 1);
//if( nextCell.getValue() !== '' ) //is empty?
nextCell.setValue(new Date());
}

if( r.getColumn() == 7 ) { //checks the column
var nextCell = r.offset(0, 1);
//if( nextCell.getValue() !== '' ) //is empty?
nextCell.setValue(new Date());
}

if( r.getColumn() == 9 ) { //checks the column
var nextCell = r.offset(0, 1);
//if( nextCell.getValue() !== '' ) //is empty?
nextCell.setValue(new Date());
}

}
}
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