SharePoint 2010 Filtered lookup is a free codeplex project. It was created by Giuseppe Marchi (peppedotnet.it).
I just came into contact with it and can’t imagine how I did all my other projects without it. This free tool allows you to do:
- Cross-site lookup (all sites within same site collection)
- Filter retrieved data using list views
- Filter retrieved data using dynamic/ad-hoc CAML queries. This means you don’t need to create a list view each time you want to apply a lookup filter to source data
- Supports retrieving data recursively using either list views or dynamic queries
- Supports MultiLookup with filtered data
- Same look and feel as default SharePoint Lookup and MultiLookup (i.e. in list forms)
What does that mean?
Cross site lookup
With a regular lookup field you can choose a field in your current site. A lot of times that is good enough, when you want to link some lists to each other. But if you want to think about “Master Data”, this field can really help. It allows you to select a site in the site collection. That means you have a much wider span of content that you can link.
If you have, for example, a list of values on your top level site, you could reuse that list in all your subsites. Think about resources, projects, tasks, …
Filter lookup
Another big advantage for this field is the possibility to filter your values. In a normal lookup field you get everything. If you have a list with 3000 items, your lookup will get slow and very long.
What if you want your users to select a training from a seminar list? You probably just want to show the seminars that are still open, happening in the future and are not fully booked. Easy peasy with this field!
The SharePoint 2010 Filterered lookup lets you filter on a CAML query or on a specific view. So this pleases both developers as business people! You can even let your endusers configure it, they just need to create a view on the list.
More information on the tool and free download here.