How to collate/merge two different lists, with the same colums into one list

Question

I have got two different lists. One is live updated by many users. The second list has the same fields and works as the master. I want to every day, at 6:00 o'clock a.m, merge List one with list two.

How could I add items from List one to list two? I want to do it by PowerShell and Timer Job.

Answer 1

Basically you have to create a new list (the merge list) the all the items from the two lists and add to the merge list:

$web = Get-SPWeb http://mysite
$list = $web.Lists["firstList"]
$merge = $web.Lists["mergeList"]
$items = $list.GetItems()

foreach ( $item in $item ) {
    # do job

    $newItem = $list.Items.Add() 
    $newItem["Title"] = $item["Title"]
    # others properties
    $newItem.Update()
}

Answer 2

Combine two lists like in the answer on SE here, or use a tutorial by Melick Rajee Baranasooriya from nothingbutsharepoint.com.

A tutorial on creating custom Timer Jobs can be found on MSDN.

Sharepoint list-synchronization with Powershell can be found on Jesper Christensen's blog.