打开Oracle Apps的主页，报下面的错误
Error Page
You have encountered an unexpected error. Please contact the System Administrator for assistance.
Click here for exception details.
点击Details，看到以下错误堆栈
Exception Details.
oracle.apps.fnd.framework.OAException: Application: FND, Message Name: FND_NO_DATABASE_CONNECTION.
at oracle.apps.fnd.framework.webui.OAPageErrorHandler.prepareException(OAPageErrorHandler.java:1251)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:2195)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:543)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:431)
at _OA._jspService(_OA.java:212)
at com.orionserver.http.OrionHttpJspPage.service(OrionHttpJspPage.java:59)
at oracle.jsp.runtimev2.JspPageTable.service(JspPageTable.java:379)
at oracle.jsp.runtimev2.JspServlet.internalService(JspServlet.java:594)
at oracle.jsp.runtimev2.JspServlet.service(JspServlet.java:518)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
at com.evermind.server.http.ResourceFilterChain.doFilter(ResourceFilterChain.java:64)
at oracle.apps.jtf.base.session.ReleaseResFilter.doFilter(ReleaseResFilter.java:26)
at com.evermind.server.http.EvermindFilterChain.doFilter(EvermindFilterChain.java:15)
at oracle.apps.fnd.security.AppsServletFilter.doFilter(AppsServletFilter.java:318)
at com.evermind.server.http.ServletRequestDispatcher.invoke(ServletRequestDispatcher.java:621)
at com.evermind.server.http.ServletRequestDispatcher.forwardInternal(ServletRequestDispatcher.java:370)
at com.evermind.server.http.HttpRequestHandler.doProcessRequest(HttpRequestHandler.java:871)
at com.evermind.server.http.HttpRequestHandler.processRequest(HttpRequestHandler.java:453)
at com.evermind.server.http.AJPRequestHandler.run(AJPRequestHandler.java:313)
at com.evermind.server.http.AJPRequestHandler.run(AJPRequestHandler.java:199)
at oracle.oc4j.network.ServerSocketReadHandler$SafeRunnable.run(ServerSocketReadHandler.java:260)
at oracle.oc4j.network.ServerSocketAcceptHandler.procClientSocket(ServerSocketAcceptHandler.java:234)
at oracle.oc4j.network.ServerSocketAcceptHandler.access$700(ServerSocketAcceptHandler.java:29)
at oracle.oc4j.network.ServerSocketAcceptHandler$AcceptHandlerHorse.run(ServerSocketAcceptHandler.java:879)
at com.evermind.util.ReleasableResourcePooledExecutor$MyWorker.run(ReleasableResourcePooledExecutor.java:303)
at java.lang.Thread.run(Thread.java:619)
## Detail 0 ##
oracle.apps.fnd.framework.OAException: Application: FND, Message Name: FND_NO_DATABASE_CONNECTION.
at oracle.apps.fnd.framework.server.OANullDBTransactionImpl.noDatabaseConnection(OANullDBTransactionImpl.java:653)
at oracle.apps.fnd.framework.server.OANullDBTransactionImpl.isLoggingEnabled(OANullDBTransactionImpl.java:930)
at oracle.apps.fnd.framework.OASessionCookieHelper.resetApplicationModule(OASessionCookieHelper.java:201)
at oracle.apps.fnd.framework.webui.OAHttpSessionCookieImpl.releaseApplicationModule(OAHttpSessionCookieImpl.java:551)
at oracle.jbo.common.ampool.SessionCookieImpl.releaseApplicationModule(SessionCookieImpl.java:642)
at oracle.apps.fnd.framework.webui.OAJSPApplicationRegistry.registerApplicationModule(OAJSPApplicationRegistry.java:275)
at oracle.apps.fnd.framework.webui.OAJSPApplicationRegistry.registerApplicationModule(OAJSPApplicationRegistry.java:78)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:1300)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:543)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:431)
at _OA._jspService(_OA.java:212)
at com.orionserver.http.OrionHttpJspPage.service(OrionHttpJspPage.java:59)
at oracle.jsp.runtimev2.JspPageTable.service(JspPageTable.java:379)
at oracle.jsp.runtimev2.JspServlet.internalService(JspServlet.java:594)
at oracle.jsp.runtimev2.JspServlet.service(JspServlet.java:518)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
at com.evermind.server.http.ResourceFilterChain.doFilter(ResourceFilterChain.java:64)
at oracle.apps.jtf.base.session.ReleaseResFilter.doFilter(ReleaseResFilter.java:26)
at com.evermind.server.http.EvermindFilterChain.doFilter(EvermindFilterChain.java:15)
at oracle.apps.fnd.security.AppsServletFilter.doFilter(AppsServletFilter.java:318)
at com.evermind.server.http.ServletRequestDispatcher.invoke(ServletRequestDispatcher.java:621)
at com.evermind.server.http.ServletRequestDispatcher.forwardInternal(ServletRequestDispatcher.java:370)
at com.evermind.server.http.HttpRequestHandler.doProcessRequest(HttpRequestHandler.java:871)
at com.evermind.server.http.HttpRequestHandler.processRequest(HttpRequestHandler.java:453)
at com.evermind.server.http.AJPRequestHandler.run(AJPRequestHandler.java:313)
at com.evermind.server.http.AJPRequestHandler.run(AJPRequestHandler.java:199)
at oracle.oc4j.network.ServerSocketReadHandler$SafeRunnable.run(ServerSocketReadHandler.java:260)
at oracle.oc4j.network.ServerSocketAcceptHandler.procClientSocket(ServerSocketAcceptHandler.java:234)
at oracle.oc4j.network.ServerSocketAcceptHandler.access$700(ServerSocketAcceptHandler.java:29)
at oracle.oc4j.network.ServerSocketAcceptHandler$AcceptHandlerHorse.run(ServerSocketAcceptHandler.java:879)
at com.evermind.util.ReleasableResourcePooledExecutor$MyWorker.run(ReleasableResourcePooledExecutor.java:303)
at java.lang.Thread.run(Thread.java:619)
oracle.apps.fnd.framework.OAException: Application: FND, Message Name: FND_NO_DATABASE_CONNECTION.
at oracle.apps.fnd.framework.server.OANullDBTransactionImpl.noDatabaseConnection(OANullDBTransactionImpl.java:653)
at oracle.apps.fnd.framework.server.OANullDBTransactionImpl.isLoggingEnabled(OANullDBTransactionImpl.java:930)
at oracle.apps.fnd.framework.OASessionCookieHelper.resetApplicationModule(OASessionCookieHelper.java:201)
at oracle.apps.fnd.framework.webui.OAHttpSessionCookieImpl.releaseApplicationModule(OAHttpSessionCookieImpl.java:551)
at oracle.jbo.common.ampool.SessionCookieImpl.releaseApplicationModule(SessionCookieImpl.java:642)
at oracle.apps.fnd.framework.webui.OAJSPApplicationRegistry.registerApplicationModule(OAJSPApplicationRegistry.java:275)
at oracle.apps.fnd.framework.webui.OAJSPApplicationRegistry.registerApplicationModule(OAJSPApplicationRegistry.java:78)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:1300)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:543)
at oracle.apps.fnd.framework.webui.OAPageBean.preparePage(OAPageBean.java:431)
at _OA._jspService(_OA.java:212)
at com.orionserver.http.OrionHttpJspPage.service(OrionHttpJspPage.java:59)
at oracle.jsp.runtimev2.JspPageTable.service(JspPageTable.java:379)
at oracle.jsp.runtimev2.JspServlet.internalService(JspServlet.java:594)
at oracle.jsp.runtimev2.JspServlet.service(JspServlet.java:518)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
at com.evermind.server.http.ResourceFilterChain.doFilter(ResourceFilterChain.java:64)
at oracle.apps.jtf.base.session.ReleaseResFilter.doFilter(ReleaseResFilter.java:26)
at com.evermind.server.http.EvermindFilterChain.doFilter(EvermindFilterChain.java:15)
at oracle.apps.fnd.security.AppsServletFilter.doFilter(AppsServletFilter.java:318)
at com.evermind.server.http.ServletRequestDispatcher.invoke(ServletRequestDispatcher.java:621)
at com.evermind.server.http.ServletRequestDispatcher.forwardInternal(ServletRequestDispatcher.java:370)
at com.evermind.server.http.HttpRequestHandler.doProcessRequest(HttpRequestHandler.java:871)
at com.evermind.server.http.HttpRequestHandler.processRequest(HttpRequestHandler.java:453)
at com.evermind.server.http.AJPRequestHandler.run(AJPRequestHandler.java:313)
at com.evermind.server.http.AJPRequestHandler.run(AJPRequestHandler.java:199)
at oracle.oc4j.network.ServerSocketReadHandler$SafeRunnable.run(ServerSocketReadHandler.java:260)
at oracle.oc4j.network.ServerSocketAcceptHandler.procClientSocket(ServerSocketAcceptHandler.java:234)
at oracle.oc4j.network.ServerSocketAcceptHandler.access$700(ServerSocketAcceptHandler.java:29)
at oracle.oc4j.network.ServerSocketAcceptHandler$AcceptHandlerHorse.run(ServerSocketAcceptHandler.java:879)
at com.evermind.util.ReleasableResourcePooledExecutor$MyWorker.run(ReleasableResourcePooledExecutor.java:303)
at java.lang.Thread.run(Thread.java:619)
解决方法：
重启应用服务器，再次打开页面，问题解决，能正常登陆。
ps:
OTN上很多人提到了要参考(Doc ID 1298103.1)来解决这个问题
R12: Login Fails Intermittently With Error "oracle.apps.fnd.framework.OAException: Application: FND, Message Name: FND_NO_DATABASE_CONNECTION" (Doc ID 1298103.1)