Archive rows to another tab greater than 3 years

Requirement is to archive all the rows older than 3 years and insert those rows into a different tab in the same spread sheet.

I have below code to archive rows to another tab where date is older than 3 years . The below code is deleting all the rows before 3 years in the source tab correctly ,but it is not inserting the deleted rows to the target tab (archived rows).please let me know how to fix this code

const ss = SpreadsheetApp.getActive()
const shSource = ss.getSheetByName('Incident Report Details')
const shTarget = ss.getSheetByName('Archived rows')

function myFunction() {
  const COL_DATE = 1
  const HEADER_HEIGHT = 1
  if(shSource.getLastRow()==HEADER_HEIGHT){
    return
  }
  const data = shSource.getRange(1+HEADER_HEIGHT,1,shSource.getLastRow()-HEADER_HEIGHT, shSource.getLastColumn())
  data.sort(COL_DATE) // prepare for deletion of continous rows
  const minDate = new Date()
  minDate.setMonth(minDate.getMonth()-36)

  
  const rowsToDelete = data.getValues().filter(row=>row[COL_DATE-1]<minDate)
  if(rowsToDelete.length>0){
    console.log(`Delete ${rowsToDelete.length} rows where date is before ${minDate}`)
    shTarget.insertRowsAfter(shTarget.getLastRow(), rowsToDelete.length)
    shTarget.getRange(shTarget.getLastRow()+1,1, rowsToDelete.length, rowsToDelete[0].length).setValues(rowsToDelete)
  } else{
    console.log(`No rows to delete`)
  }

  shSource.deleteRows(HEADER_HEIGHT+1, rowsToDelete.length)
}

Updated answer:

Your code is working fine for me. Just added the deleteRows statement inside IF.

const ss = SpreadsheetApp.getActive()
const shSource = ss.getSheetByName('Incident Report Details')
const shTarget = ss.getSheetByName('Archived rows')

function myFunction() {
  const COL_DATE = 1
  const HEADER_HEIGHT = 1
  if (shSource.getLastRow() == HEADER_HEIGHT) {
    return
  }
  const data = shSource.getRange(1 + HEADER_HEIGHT, 1, shSource.getLastRow() - HEADER_HEIGHT, shSource.getLastColumn())
  shSource.sort(COL_DATE) // prepare for deletion of continous rows
  const minDate = new Date()
  minDate.setMonth(minDate.getMonth() - 36)


  const rowsToDelete = data.getValues().filter(row => row[COL_DATE - 1] < minDate)
  console.log('rowsToDelete: ' + rowsToDelete.length);

  if (rowsToDelete.length > 0) {
    console.log(`Delete ${rowsToDelete.length} rows where date is before ${minDate}`)
    shTarget.insertRowsAfter(shTarget.getLastRow(), rowsToDelete.length)
    shTarget.getRange(shTarget.getLastRow() + 1, 1, rowsToDelete.length, rowsToDelete[0].length).setValues(rowsToDelete)
    shSource.deleteRows(HEADER_HEIGHT + 1, rowsToDelete.length)
  } else {
    console.log(`No rows to delete`)
  }
}

Earlier answer (Please ignore):

Add this line before deleting rows

SpreadsheetApp.flush();

Spreadsheet operations are sometimes bundled together to improve performance. However, sometimes you may want to make sure that all pending changes are made right away as a scriptYour code is executingworking fine for me.