Some error from using JDBC to develop SciDB


#1

JDBC, java 1.6 , centos 6.5
AFL Functions: concat(build(<x:double>[i=0:3,4,0,j=0:2,1,0],1), build(<x:double>[i=0:1,4,0,j=0:2,1,0],2))

when I use this function to show result …it will return error …

Error:java.sql.SQLException: java.lang.ClassCastException: org.scidb.io.network.Message$Error cannot be cast to org.scidb.io.network.Message$Chunk


#2

Hey the reply may be late… but hope it helps others who also encountered this.

I downloaded the SciDB JDBC from the Maven repository, which has the version code of 1.0 (the only one there is). And I encountered the same problem. I’m pretty sure that this is a bug.

To circumvent the problem and have the data returned to you, you need to make sure that the actual dimension value spans of your result fit inside a chunk.

For example, this should give you the same exception:
build([i=0:3,4,0,j=0:2,1,0],1)

And this should be fine:
build([i=0:3,4,0,j=0:2,**3**,0],1)

Your iquery should have no problem with either of these queries.

I checked the JDBC package released with 14.12, and I think it also has the same issue. Since there was no follow up to this question from the SciDB team, I’m not sure if the JDBCs of the newer versions solved the problems.