The activity stream lives in its own tables with its own query class, so every WordPress instinct about WP_Query, post meta and the loop is wrong here. The…
The activity stream is not posts. It has its own table, its own class and its own template loop, so every habit built around WP_Query — pre_get_posts, fields…
BuddyPress extended profile fields look like user meta and are not. They live in their own tables — bp_xprofile_fields for the definitions, bp_xprofile_data for one row per field…
A community site’s posts table stays in the tens of thousands while bp_activity reaches millions, because it records everything: an update, a comment, a friendship, a group join,…
Everything else in a WordPress install is a post, so the first instinct with a BuddyPress group is a WP_Query against some post type. There is not one.…