db-derby-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Kim Haase <Camilla.Ha...@Sun.COM>
Subject Re: STDDEV for Derby
Date Fri, 14 Mar 2008 22:09:56 GMT
It's actually the topic "Aggregates (set functions)" 
(http://db.apache.org/derby/docs/dev/ref/rrefsqlj33923.html). If the 
statement is incorrect, we should fix it.

Kim

Rick Hillegas wrote:
> Hi Art,
> 
> Can you tell us what section of the Reference Guide makes this claim? 
> The old Cloudscape engine offered syntax for creating user-defined 
> aggregates but that machinery does not work in Derby. There is a JIRA 
> for this feature: DERBY-672. You may be able to do what you need by 
> using Derby functions. If you search the codeline for 
> "getMedianTestScore", you will find an example of how to code an 
> aggregating function which compute a median value over a set of rows.
> 
> Hope this helps,
> -Rick
> 
> Art Majtenyi wrote:
>>
>> Reference manual says, "You can also create your own aggregates to 
>> perform other set functions such as calculating the standard deviation."
>> Has anyone done this?...Is there any docs to help with this?...It's 
>> not as easy as a scalar function.
>>
>> Art Majtenyi, amajteny@us.ibm.com
>> WebSphere Business Monitor Development
>> IBM Corporation, RTP, NC
>> O: 919/254-4443, M: 919/302-8827
>>
> 

Mime
View raw message