Union Operator

[Michael Alexeev]

Hi All,

Does VoltDB support UNION operator? I have a simple query like
SELECT PKEY FROM A union  SELECT PKEY FROM B

and I am getting the following exception while trying to compile it:

2012-06-15 21:10:56,914   INFO  [main] COMPILER: [Select.class]: Compiling Statement: SELECT PKEY FROM A union  SELECT PKEY FROM B
java.lang.ClassCastException: org.hsqldb_voltpatches.QueryExpression cannot be cast to org.hsqldb_voltpatches.QuerySpecification
    at org.hsqldb_voltpatches.StatementQuery.voltGetXML(StatementQuery.java:184)
    at org.hsqldb_voltpatches.HSQLInterface.getXMLCompiledStatement(HSQLInterface.java:176)
    at org.voltdb.planner.QueryPlanner.compilePlan(QueryPlanner.java:117)
    at org.voltdb.compiler.StatementCompiler.compile(StatementCompiler.java:109)
    at org.voltdb.compiler.ProcedureCompiler.compileJavaProcedure(ProcedureCompiler.java:213)
    at org.voltdb.compiler.ProcedureCompiler.compile(ProcedureCompiler.java:67)
    at org.voltdb.compiler.VoltCompiler.compileDatabaseNode(VoltCompiler.java:681)
    at org.voltdb.compiler.VoltCompiler.compileXMLRootNode(VoltCompiler.java:488)
    at org.voltdb.compiler.VoltCompiler.compileCatalog(VoltCompiler.java:447)
    at org.voltdb.compiler.VoltCompiler.compile(VoltCompiler.java:325)
    at org.voltdb.compiler.VoltCompiler.main(VoltCompiler.java:1212)
2012-06-15 21:10:56,915   ERROR [main] COMPILER: [Select.class]: Failed to plan for stmt: selectItem

Thanks,
Mike

[Ryan Betts]

No - I think there might be a half-done union operator somewhere in
the EE, but as far as I know, we don't plan Union.

[Michael Alexeev]

Thanks Ryan. yes, there is a union executor there so I thought it's supported. Out of curiosity, Are there plans to support it?
Mike

[Ryan Betts]

On Fri, Jun 15, 2012 at 9:51 PM, Michael Alexeev
<michael...@gmail.com> wrote:
> Thanks Ryan. yes, there is a union executor there so I thought it's
> supported. Out of curiosity, Are there plans to support it?
> Mike

Not in the near term, as far as I'm aware?
Ryan.

[John Piekos]

I've created ticket ENG-3217 for the ClassCastException.  

Thanks for finding this, Michael.  

John

--
John Piekos
VoltDB, Inc.  
Vice President, Engineering
email:  jpi...@voltdb.com 
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