Forum: Building VoltDB Applications

Post: 10 MB query limit

10 MB query limit
May 13, 2011
In the Select statement doc I noticed that: "Extremely large result sets (greater than 10 megabytes in size) are not supported. If you execute a SELECT statement that generates a result set of more than 10 megabytes, VoltDB will return an error."

10 MB isn't "extremely large". If I have 200 bytes in a row, that's only 50,000 rows that I can process (e.g. rank) in one shot. 50,000 rows is tiny.

What is the best way to rank ~300,000 users (userid) when I need to sum a particular column grouping by userid and then use the resulting sum to perform a rank for all users?

I'm afraid the data set could easily exceed 10MB with that many users and I don't relish the thought of spawning and closing many requests just to avoid a request limit (10 MB)that seems really small.

Thanks in advance for ideas.
re: 10BM query limit
May 13, 2011

I just responded to a similar question in your other posting at

To provide more information on this exact question can you please include some schema and the SQL you'd execute to produce the result you are interested in?

50 megabyte limit as of v2.0
Nov 16, 2011
Note that as of VoltDB v2.0 this limit is now 50mb.