A class that extends the SelectQueryBuilder should be created that allows selecting results from all three tables that will contain results (cu_changes, cu_private_event and cu_log_event). This query builder should make the process of creating a query for results relatively easy and should try to keep as close to the structure of the builder.

The intent is that usages of this builder should be able to either run the query using the builder (for the rest API) or by exporting it's query info (for Special:CheckUser and Special:Investigate). The API may use the query info method but I have not investigated that fully.

Splitting the parent task into multiple tasks to make organisation easier.