2015-11-02 19:14 GMT-03:00 droberts <david.roberts@xxxxxxxxxxxx>:
Hi, I have a table that contains call records. I'm looking to get only
records for users who made the most calls over a particular time duration in
an efficient way.
calls()
time, duration, caller_number, dialed_number
-- query to get top 10 callers
select caller_number, count(1) from calls group by caller_number order by
calls desc limit 10
--my current query to get those callers
select * from call where caller_number in (above query)
It works but I was hoping for something a little more efficient if anyone
has an idea.
I think that almost every time based tables, should be partitioned. Also, depending on your workload you can create lazy views over the last entries in calls table during a particular time frame.
Probably in this particular case, you will want to dig into more underneath design in order to get the best performance.
Doing a lazy view with that query, you can use the top n of it and get less callers if you need to (or more if you want to expand the feature).
Hope it helps,
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