Automatically updating list from another list in child site

Question

I have a list called 'Mobile Phone Tracker' in my subsite with employee name and mobile numbers and other details. I need to create another list 'Mobile Phone Directory' in my site (parent site) with only name and mobile number which can be used as a mobile phone directory. The new list must update from the 'Mobile Phone Tracker'list automatically as i update it. Can any one help me with this. Thanks.

Answer 1

Options for this would be to:

1. Use an event receiver that is attached to each 'Mobile Phone Tracker' list. On added/updated/deleted, update the Mobile Phone Directory list.
2. Just use Search. Create a content type to use on all Mobile Phone Tracker lists. Index all Mobile Phone Tracker Lists. Configure the Mobile Phone Directory as a search for items of the the content type used on the Mobile Phone Tracker. This approach would have some latency (while search indexes the new or updated content), but it's probably simplest, and it means you've only got one copy of your data.

I've done both at different times, and I think the second works better.