Steven Zahm@ Gopal
Apologies for the tardy reply!
In regards to 4,5,6…
4. Nothing out of box. The Connections core can support such queries but there is nothing available yet that is plugin and play. Other devs of custom coded thos feature to meet their needs.
5. All the templates that feature the searchable category drop down contain a beta feature (which works quite well) that allows the selection of multiple categories. When this feature is enabled, the query is an operational ‘AND’ query. So in short, yes.
6. Not in the current release version. The next release which is due out really soon does and an API which devs can use to add custom field support. This next release does not contain a point and click way to create custom fields, they would have to be added by a dev. There are already a few dev that are using a pre-release version of Connections on client sites that utilize this new feature to great success. This is basically the status of the custom fields support. At this point I consider it finished for the next release.
re: performance:
My test database is on a little over 25k entries and it performs quite well. I do know that there are users with 30-50k and it works fines for them too. I am not aware of any installation with 500k so I do not have a solid answer for you. Sorry. The best I can say is that I’ve done my best to model the queries after the WordPress core queries so if those scale will, my should too.
I hope that helps!