KNIME error when loading Dremio JDBC Driver

bodhibyte · August 20, 2018, 10:03pm

Hi,

When I try to load the Dremio JDBC driver in the latest KNIME 3.6.0, I’m seeing the error below, even after closing and restarting KNIME. This error doesn’t show up in the knime.log when I remove the JDBC driver. I’ve successfully used the Dremio JDBC Driver in dbeaver (also built on Eclipse RCP) without any issue.

Is anyone able to get the Dremio JDBC Driver in KNIME? If not, where can I submit a bug report?

Thanks!

2018-08-17 01:07:19,430 : DEBUG : main : DatabaseDriverLoader :  :  : Load driver from file: /Users/bodhi/jdbc_drivers/dremio-jdbc-driver-2.0.5-201806021755080191-767cfb5.jar
2018-08-17 01:07:22,980 : ERROR : main : KNIMECorePlugin :  :  : Error while starting workbench, some setting may not have been applied properly: null
2018-08-17 01:07:22,983 : DEBUG : main : KNIMECorePlugin :  :  : Error while starting workbench, some setting may not have been applied properly: null
java.lang.NullPointerException
	at com.dremio.jdbc.proxy.TracingProxyDriver.getMajorVersion(TracingProxyDriver.java:270)
	at org.knime.core.node.port.database.DatabaseWrappedDriver.getInfo(DatabaseWrappedDriver.java:155)
	at org.knime.core.node.port.database.DatabaseWrappedDriver.getInfo(DatabaseWrappedDriver.java:141)
	at org.knime.core.node.port.database.DatabaseDriverLoader.readZipFiles(DatabaseDriverLoader.java:297)
	at org.knime.core.node.port.database.DatabaseDriverLoader.readZip(DatabaseDriverLoader.java:261)
	at org.knime.core.node.port.database.DatabaseDriverLoader.loadDriver(DatabaseDriverLoader.java:241)
	at org.knime.core.node.port.database.DatabaseDriverLoader.loadDriver(DatabaseDriverLoader.java:225)
	at org.knime.workbench.core.KNIMECorePlugin.initDatabaseDriver(KNIMECorePlugin.java:275)
	at org.knime.workbench.core.KNIMECorePlugin.start(KNIMECorePlugin.java:260)
	at org.eclipse.osgi.internal.framework.BundleContextImpl$3.run(BundleContextImpl.java:774)
	at org.eclipse.osgi.internal.framework.BundleContextImpl$3.run(BundleContextImpl.java:1)
	at java.security.AccessController.doPrivileged(Native Method)
	at org.eclipse.osgi.internal.framework.BundleContextImpl.startActivator(BundleContextImpl.java:767)
	at org.eclipse.osgi.internal.framework.BundleContextImpl.start(BundleContextImpl.java:724)
	at org.eclipse.osgi.internal.framework.EquinoxBundle.startWorker0(EquinoxBundle.java:932)
	at org.eclipse.osgi.internal.framework.EquinoxBundle$EquinoxModule.startWorker(EquinoxBundle.java:309)
	at org.eclipse.osgi.container.Module.doStart(Module.java:581)
	at org.eclipse.osgi.container.Module.start(Module.java:449)
	at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:470)
	at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:107)
	at org.eclipse.osgi.internal.loader.classpath.ClasspathManager.findLocalClass(ClasspathManager.java:529)
	at org.eclipse.osgi.internal.loader.ModuleClassLoader.findLocalClass(ModuleClassLoader.java:325)
	at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:345)
	at org.eclipse.osgi.internal.loader.sources.SingleSourcePackage.loadClass(SingleSourcePackage.java:36)
	at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:419)
	at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:372)
	at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:364)
	at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:161)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	at java.lang.Class.getDeclaredConstructors0(Native Method)
	at java.lang.Class.privateGetDeclaredConstructors(Class.java:2671)
	at java.lang.Class.getConstructor0(Class.java:3075)
	at java.lang.Class.newInstance(Class.java:412)
	at org.eclipse.osgi.internal.framework.BundleContextImpl.loadBundleActivator(BundleContextImpl.java:758)
	at org.eclipse.osgi.internal.framework.BundleContextImpl.start(BundleContextImpl.java:711)
	at org.eclipse.osgi.internal.framework.EquinoxBundle.startWorker0(EquinoxBundle.java:932)
	at org.eclipse.osgi.internal.framework.EquinoxBundle$EquinoxModule.startWorker(EquinoxBundle.java:309)
	at org.eclipse.osgi.container.Module.doStart(Module.java:581)
	at org.eclipse.osgi.container.Module.start(Module.java:449)
	at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:470)
	at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:107)
	at org.eclipse.osgi.internal.loader.classpath.ClasspathManager.findLocalClass(ClasspathManager.java:529)
	at org.eclipse.osgi.internal.loader.ModuleClassLoader.findLocalClass(ModuleClassLoader.java:325)
	at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:345)
	at org.eclipse.osgi.internal.loader.sources.SingleSourcePackage.loadClass(SingleSourcePackage.java:36)
	at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:419)
	at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:372)
	at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:364)
	at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:161)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	at org.knime.product.rcp.KNIMEApplicationActionBarAdvisor.makeActions(KNIMEApplicationActionBarAdvisor.java:208)
	at org.eclipse.ui.application.ActionBarAdvisor.fillActionBars(ActionBarAdvisor.java:149)
	at org.knime.product.rcp.KNIMEApplicationActionBarAdvisor.fillActionBars(KNIMEApplicationActionBarAdvisor.java:487)
	at org.eclipse.ui.internal.WorkbenchWindow.fillActionBars(WorkbenchWindow.java:2583)
	at org.eclipse.ui.internal.WorkbenchWindow.setup(WorkbenchWindow.java:667)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:55)
	at org.eclipse.e4.core.internal.di.InjectorImpl.processAnnotated(InjectorImpl.java:966)
	at org.eclipse.e4.core.internal.di.InjectorImpl.inject(InjectorImpl.java:151)
	at org.eclipse.e4.core.internal.di.InjectorImpl.inject(InjectorImpl.java:118)
	at org.eclipse.e4.core.contexts.ContextInjectionFactory.inject(ContextInjectionFactory.java:73)
	at org.eclipse.ui.internal.Workbench.createWorkbenchWindow(Workbench.java:1525)
	at org.eclipse.ui.internal.Workbench.openWorkbenchWindow(Workbench.java:2653)
	at org.eclipse.ui.internal.Workbench.getWorkbenchPage(Workbench.java:2083)
	at org.eclipse.ui.internal.Workbench.setReference(Workbench.java:2131)
	at org.eclipse.ui.internal.Workbench.access$28(Workbench.java:2099)
	at org.eclipse.ui.internal.Workbench$35.handleEvent(Workbench.java:2021)
	at org.eclipse.e4.ui.services.internal.events.UIEventHandler$1.run(UIEventHandler.java:40)
	at org.eclipse.swt.widgets.Synchronizer.syncExec(Synchronizer.java:233)
	at org.eclipse.ui.internal.UISynchronizer.syncExec(UISynchronizer.java:145)
	at org.eclipse.swt.widgets.Display.syncExec(Display.java:4806)
	at org.eclipse.e4.ui.internal.workbench.swt.E4Application$1.syncExec(E4Application.java:211)
	at org.eclipse.e4.ui.services.internal.events.UIEventHandler.handleEvent(UIEventHandler.java:36)
	at org.eclipse.equinox.internal.event.EventHandlerWrapper.handleEvent(EventHandlerWrapper.java:201)
	at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:197)
	at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:1)
	at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:230)
	at org.eclipse.osgi.framework.eventmgr.ListenerQueue.dispatchEventSynchronous(ListenerQueue.java:148)
	at org.eclipse.equinox.internal.event.EventAdminImpl.dispatchEvent(EventAdminImpl.java:135)
	at org.eclipse.equinox.internal.event.EventAdminImpl.sendEvent(EventAdminImpl.java:78)
	at org.eclipse.equinox.internal.event.EventComponent.sendEvent(EventComponent.java:39)
	at org.eclipse.e4.ui.services.internal.events.EventBroker.send(EventBroker.java:94)
	at org.eclipse.e4.ui.internal.workbench.UIEventPublisher.notifyChanged(UIEventPublisher.java:60)
	at org.eclipse.emf.common.notify.impl.BasicNotifierImpl.eNotify(BasicNotifierImpl.java:374)
	at org.eclipse.e4.ui.model.application.ui.basic.impl.PartImpl.setContext(PartImpl.java:431)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:626)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$1.run(PartRenderingEngine.java:536)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:520)
	at org.eclipse.e4.ui.workbench.renderers.swt.ElementReferenceRenderer.createWidget(ElementReferenceRenderer.java:70)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createWidget(PartRenderingEngine.java:975)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:651)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
	at org.eclipse.e4.ui.workbench.renderers.swt.StackRenderer.showTab(StackRenderer.java:1317)
	at org.eclipse.e4.ui.workbench.renderers.swt.LazyStackRenderer.postProcess(LazyStackRenderer.java:103)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:669)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
	at org.eclipse.e4.ui.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashRenderer.processContents(SashRenderer.java:142)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
	at org.eclipse.e4.ui.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashRenderer.processContents(SashRenderer.java:142)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
	at org.eclipse.e4.ui.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
	at org.eclipse.e4.ui.workbench.renderers.swt.PerspectiveRenderer.processContents(PerspectiveRenderer.java:49)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
	at org.eclipse.e4.ui.workbench.renderers.swt.PerspectiveStackRenderer.showTab(PerspectiveStackRenderer.java:82)
	at org.eclipse.e4.ui.workbench.renderers.swt.LazyStackRenderer.postProcess(LazyStackRenderer.java:103)
	at org.eclipse.e4.ui.workbench.renderers.swt.PerspectiveStackRenderer.postProcess(PerspectiveStackRenderer.java:63)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:669)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
	at org.eclipse.e4.ui.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
	at org.eclipse.e4.ui.workbench.renderers.swt.SashRenderer.processContents(SashRenderer.java:142)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
	at org.eclipse.e4.ui.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
	at org.eclipse.e4.ui.workbench.renderers.swt.WBWRenderer.processContents(WBWRenderer.java:725)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1059)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1022)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:150)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:687)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:604)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:148)
	at org.knime.product.rcp.KNIMEApplication.start(KNIMEApplication.java:141)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:388)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:243)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:673)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:610)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1519)

bodhibyte · August 21, 2018, 4:57am

I’ve also posted this on the KNIME forum and they believe this is an issue with the Dremio JDBC driver.

Is anyone able to help?

laurent · August 21, 2018, 5:06am

I’m not familiar with KNIME software, but it looks like it’s not using the Dremio driver class com.dremio.jdbc.Driver.

bodhibyte · August 21, 2018, 5:22am

Thanks, laurent, for the quick reply.

I’m not sure if this is helpful, but if I’m not mistaken, the line of code that appears to be failing is here:

github.com

dremio/dremio-oss/blob/a01f82bdfb95e6502d6e08a2451e52a5f9454afa/client/jdbc/src/main/java/com/dremio/jdbc/proxy/TracingProxyDriver.java#L270


}


@Override
public DriverPropertyInfo[] getPropertyInfo( String url, Properties info )
    throws SQLException {
  return proxyDriver.getPropertyInfo( url, info );
}


@Override
public int getMajorVersion() {
  return proxyDriver.getMajorVersion();
}


@Override
public int getMinorVersion() {
  return proxyDriver.getMinorVersion();
}
@Override
public boolean jdbcCompliant() {
  return proxyDriver.jdbcCompliant();
}

laurent · August 21, 2018, 5:33am

But like I said before, that class is not the Dremio JDBC driver class, so you should check with KNIME documentation on how to set the Driver class to be com.dremio.jdbc.Driver (DBeaver has such an option).

Or it might be that KNIME has some kind of discovery process which involves finding all the drivers classes in a jar, instantiating them and trying to get information from them. Unfortunately the class you mentioned above is a special one, which is not supposed to be used as-is, which is why it’s not advertised by the jar using Java Service provider framework (which is how JDBC drivers are usually discovered, see https://docs.oracle.com/javase/7/docs/api/java/sql/DriverManager.html). I would recommend working with KNIME support/community to resolve that issue then.

bodhibyte · August 21, 2018, 6:00am

Thank you, Laurent. I’ll follow up with KNIME.

Interestingly enough, I found that the code for the Apache Drill JDBC has the same class with the same method here:

github.com

apache/drill/blob/8a1a7c53fb211dcba6e7b2f2ce90c28af4b9c518/exec/jdbc/src/main/java/org/apache/drill/jdbc/proxy/TracingProxyDriver.java#L272


}


@Override
public DriverPropertyInfo[] getPropertyInfo( String url, Properties info )
    throws SQLException {
  return proxyDriver.getPropertyInfo( url, info );
}


@Override
public int getMajorVersion() {
  return proxyDriver.getMajorVersion();
}


@Override
public int getMinorVersion() {
  return proxyDriver.getMinorVersion();
}
@Override
public boolean jdbcCompliant() {
  return proxyDriver.jdbcCompliant();
}

However, I’m able to use the Apache Drill JDBC driver in KNIME without any issues.

bodhibyte · August 21, 2018, 7:19am

Laurent,

I’ve heard back from thor on the KNIME thread, please see my post and his response pasted below:

bodhibyte
I just installed the new KNIME Labs Database bundle. When I click on “Find driver classes”, as you can see, I’m getting:

ERROR DriverEditorDialog java.lang.NullPointerException

[

I have no problem loading this JDBC driver in dbeaver, it has a similar dialog and allows me to specify the class name as com.dremio.jdbc.Driver which works without any issues.
[Missing image in post below]

thor KNIME Team Member
DBeaver probably doesn’t attempt to get the major version from the instantiated driver which is a perfectly valid operation and must not throw a NPE.

bodhibyte · August 21, 2018, 7:22am

Second image for post above.

jduong · August 21, 2018, 4:20pm

@bodhibyte,

Does KNIME allow you to pick your Java driver class? It’s odd that the TracingProxyDriver is getting used.

laurent · August 21, 2018, 5:25pm

I agree with the KNIME member that getting the major version of a working driver is a perfectly valid operation, but the class they are instantiating is not a working driver as it is used for debugging purpose.

Maybe as a workaround you can manually remove that class from the jar?

bodhibyte · August 28, 2018, 6:31am

Sorry for the delay, my posts got flagged as spam because of the embedded links to github.

@jduong Unfortunately I can’t manually select a class as according to thor (KNIME team member on the forum)

“We scan the driver Jar for potential driver classes and therefore instantiate any class that implements java.sql.Driver.”

My guess is that it’s instantiating an object of each of the classes that implement the java.sql.Driver and then calling the getMajorVersion method to populate the list before I’m able to select the class.

I’ve referred them to the DBeaver code here as they might be able to reuse their find class functionality.

allan.sene · July 15, 2019, 7:13pm

Any update on this? We are willing to use Knime with Dremio connecting directly with JDBC Driver, but we’re not sure if it is stable or not.

laurent · July 15, 2019, 7:54pm

Dremio JDBC driver is production ready, and the driver metadata only exports com.dremio.jdbc.Driver as a JDBC driver.

Unfortunately KNIME do not use metadata but relies on its own mechanism to detect JDBC drivers and misidentifies an internal class as a valid driver. You should work with KNIME to get this addressed.

tobias.koetter · August 16, 2019, 8:00am

Hi,
the new database framework that we have released with KNIME Analytics Platform 4.0 now allows the user to select the driver class to use when registering a new driver. For further details see this section of the KNIME database documentation.
Bye
Tobias

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