Hi Swapnil,
The Using VoltDB Guide describes supported SQL for VoltDB in Appendix B. The docs can be found at:
https://community.voltdb.com/sites/default/files/UsingVoltDB.pdf
User defined functions are not currently supported, but may be in a future release. If you can give more detail about the functions you are interested in, we may be able to help you include that logic within a stored procedure.
Regards,
Bobbi
Hi Bobbi,
I just meant it as a general query about features, but thanks for the offer.
I have one more general query - in a new thread.
Thanks,
Swapnil
Swapnil,
Just to follow up on Bobbi's response.
We currently support SUM(), MIN(), MAX(), COUNT(), and AVG() aggregate functions. We do not have any single-row SQL functions at this point. VoltDB stored procedures are extremely efficient and you can easily implement TRUNC(), ROUND(), NVL(), DECODE(), etc. functionality within Java. We do plan on adding single-row SQL functions to our supported SQL as we get feedback from the community.
Are there any SQL functions that you find invaluable?
-Tim
Is a Java implemented round() in a stored procedure always going to be as fast as a (coming) VoltDB built-in function? Because VoltDB is written in Java anyway?
Or will there be performance advantages of built-in functions in the future?
Henning,
There will be a minor performance advantage to having single-row SQL functions, as in the following:
select round(a.quantity * a.price,2) as value from a where a.order_id = 5; To implement this in Java I'll have to bring back the value of a.quantity as well as a.price, so I'll have some additional overhead. However, this is already very fast in VoltDB.
As users build VoltDB applications we will prioritise the additional functionality according to need.
-Tim
Where should we post enhancement requests?
I would like some bit operators:
select * from <table> where <col> band 0x0011 > 0;
This would give us an OR-clause functionality suitable for our current needs.
