Should I use the Infobright database or is there a better aggregation solution?
Almost always (in my experience), the following is the solution to performance with large, log-like, data and semi ad hoc queries.

Characteristics of the data and the application:


continually arriving data
no updates to 'old' data
optionally purging old data (if so use PARTITION BY RANGE(TO_DAYS()))
queries tend to have a date range in the WHERE clause


Solution:  Build and maintain "summary tables".


pick a timeframe (usually day or hour)
after midnight (or top of hour), summarize yesterday's data from the raw (Fact) table into the Summary table.
PK of the Summary table usually includes some dimension(s) and the rounded-down date/hour.
rest of fields include aggregates like COUNT(), SUM(), etc, but not AVG().
AVG is calculated as SUM(sum_foo)/SUM(ct)
"reports" hit a summary table, not the fact table.
1-10 summary tables usually suffice for a given application
Querying the summary table usually gives you 10x performance improvement; I have seen 1000x in rare cases.


I say "semi ad hoc" because you will find out that users don't really query on everything.  Even if they do, you can have summary table(s) that at least help.

I mentioned the straight-forward way of completely summarizing "yesterday".  There are many other flavors.  One is "as needed", with the aid of INSERT ... ON DUPLICATE KEY UPDATE.