如何在Birt报告中使用嵌套案例。 以下查询工作正常，具有单例。
SELECT RD_DEVT.RDT_ORDERDETAIL.ACTIONSTATUS, RD_DEVT.RDT_ORDERDETAIL.REFLINENUM AS REFLINENUM,
(CASE
WHEN RD_DEVT.RDT_ORDERDETAIL.ACTIONSTATUS IN (8) THEN 1
WHEN RD_DEVT.RDT_ORDERDETAIL.ACTIONSTATUS IN (6) THEN 2
ELSE 5
END) AS ASTATUS
FROM RD_DEVT.RDT_ORDER, RD_DEVT.RDT_ORDERDETAIL
WHERE RD_DEVT.RDT_ORDER.ID = ? AND RD_DEVT.RDT_ORDER.ID = RD_DEVT.RDT_ORDERDETAIL.ORDID
AND RD_DEVT.RDT_ORDERDETAIL.LATEST = 1
ORDER BY ASTATUS, REFLINENUM
但是下面的查询会在Birt报告中抛出异常，这有多种情况。
SELECT RD_DEVT.RDT_ORDERDETAIL.ACTIONSTATUS, RD_DEVT.RDT_ORDERDETAIL.REFLINENUM AS REFLINENUM,
(
CASE WHEN 'Buyer' = ? THEN
(CASE
WHEN RD_DEVT.RDT_ORDERDETAIL.ACTIONSTATUS IN (3) THEN 1
WHEN RD_DEVT.RDT_ORDERDETAIL.ACTIONSTATUS IN (4) THEN 2
ELSE 3
END)
ELSE
(CASE
WHEN RD_DEVT.RDT_ORDERDETAIL.ACTIONSTATUS IN (8) THEN 1
WHEN RD_DEVT.RDT_ORDERDETAIL.ACTIONSTATUS IN (6) THEN 2
ELSE 5
END)END
) AS ASTATUS
FROM RD_DEVT.RDT_ORDER, RD_DEVT.RDT_ORDERDETAIL
WHERE RD_DEVT.RDT_ORDER.ID = ? AND RD_DEVT.RDT_ORDER.ID = RD_DEVT.RDT_ORDERDETAIL.ORDID
AND RD_DEVT.RDT_ORDERDETAIL.LATEST = 1
ORDER BY ASTATUS, REFLINENUM
如果我尝试保存Above Query，则会显示NullPointerException 它不会像 SQL选择查询之类的输出列，计算列
但如果我改变条件，例如＆＃39;买方＆＃39; =＆＃39;＆＃39;它有效。
例外：
java.lang.NullPointerException
at org.eclipse.datatools.modelbase.sql.query.helper.DataTypeHelper.getJDBCTypeForNamedType(DataTypeHelper.java:92)
at org.eclipse.birt.report.data.oda.jdbc.dbprofile.ui.internal.sqb.SQLQueryUtility.getJDBCTypeCode(SQLQueryUtility.java:543)
at org.eclipse.birt.report.data.oda.jdbc.dbprofile.ui.internal.sqb.SQLQueryUtility.convertToDataElementAttributes(SQLQueryUtility.java:509)
at org.eclipse.birt.report.data.oda.jdbc.dbprofile.ui.internal.sqb.SQLQueryUtility.updateParameterDesign(SQLQueryUtility.java:468)
at org.eclipse.birt.report.data.oda.jdbc.dbprofile.ui.internal.sqb.SQLQueryUtility.updateQueryMetaData(SQLQueryUtility.java:182)
at org.eclipse.birt.report.data.oda.jdbc.dbprofile.ui.internal.sqb.SQLQueryUtility.updateDataSetDesign(SQLQueryUtility.java:106)
at org.eclipse.birt.report.data.oda.jdbc.dbprofile.ui.internal.sqb.SQBDataSetWizardPage.collectDataSetDesign(SQBDataSetWizardPage.java:394)
at org.eclipse.datatools.connectivity.oda.design.internal.ui.DataSetWizardPageCore.finishDataSetDesign(DataSetWizardPageCore.java:395)
at org.eclipse.datatools.connectivity.oda.design.internal.ui.DataSetWizardBase.collectDataSetDesignFromPage(DataSetWizardBase.java:365)
at org.eclipse.datatools.connectivity.oda.design.internal.ui.DataSetWizardBase.finishDataSetDesign(DataSetWizardBase.java:387)
at org.eclipse.datatools.connectivity.oda.design.internal.ui.DataSetWizardBase.getResponseSession(DataSetWizardBase.java:123)
at org.eclipse.datatools.connectivity.oda.design.internal.designsession.DataSetDesignSessionBase.finishDataSetDesign(DataSetDesignSessionBase.java:442)
at org.eclipse.datatools.connectivity.oda.design.internal.designsession.DataSetDesignSessionBase.flush(DataSetDesignSessionBase.java:237)
at org.eclipse.datatools.connectivity.oda.design.ui.designsession.DataSetDesignSession.flush(DataSetDesignSession.java:136)
at org.eclipse.birt.report.designer.data.ui.dataset.PropertyPageWrapper.canLeave(PropertyPageWrapper.java:118)
at org.eclipse.birt.report.designer.data.ui.dataset.PropertyPageWrapper.performOk(PropertyPageWrapper.java:95)
at org.eclipse.birt.report.designer.data.ui.property.AbstractPropertyDialog.okPressed(AbstractPropertyDialog.java:771)
at org.eclipse.birt.report.designer.data.ui.property.AbstractPropertyDialog.okPressed(AbstractPropertyDialog.java:756)
at org.eclipse.birt.report.designer.data.ui.dataset.DataSetEditor.okPressed(DataSetEditor.java:680)
at org.eclipse.birt.report.designer.data.ui.property.AbstractPropertyDialog.buttonPressed(AbstractPropertyDialog.java:637)
at org.eclipse.jface.dialogs.Dialog$2.widgetSelected(Dialog.java:624)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:228)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3910)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3503)
at org.eclipse.jface.window.Window.runEventLoop(Window.java:825)
at org.eclipse.jface.window.Window.open(Window.java:801)
at org.eclipse.birt.report.designer.ui.dialogs.BaseDialog.open(BaseDialog.java:110)
at org.eclipse.birt.report.designer.data.ui.providers.EditableDataSetNodeProvider.performEdit(EditableDataSetNodeProvider.java:99)
at org.eclipse.birt.report.designer.internal.ui.views.DefaultNodeProvider.performRequest(DefaultNodeProvider.java:432)
at org.eclipse.birt.report.designer.internal.ui.views.actions.EditAction.doAction(EditAction.java:90)
at org.eclipse.birt.report.designer.internal.ui.views.actions.AbstractElementAction.run(AbstractElementAction.java:70)
at org.eclipse.birt.report.designer.internal.ui.views.RenameListener.doubleClick(RenameListener.java:214)
at org.eclipse.jface.viewers.StructuredViewer$1.run(StructuredViewer.java:821)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.runtime.Platform.run(Platform.java:888)
at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:48)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
at org.eclipse.jface.viewers.StructuredViewer.fireDoubleClick(StructuredViewer.java:819)
at org.eclipse.jface.viewers.AbstractTreeViewer.handleDoubleSelect(AbstractTreeViewer.java:1419)
at org.eclipse.jface.viewers.StructuredViewer$4.widgetDefaultSelected(StructuredViewer.java:1195)
at org.eclipse.jface.util.OpenStrategy.fireDefaultSelectionEvent(OpenStrategy.java:238)
at org.eclipse.jface.util.OpenStrategy.access$0(OpenStrategy.java:235)
at org.eclipse.jface.util.OpenStrategy$1.handleEvent(OpenStrategy.java:296)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3910)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3503)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2405)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2369)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2221)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:500)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:493)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:113)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:194)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:368)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:559)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:514)
at org.eclipse.equinox.launcher.Main.run(Main.java:1311)