我正在一个java项目中工作，我们使用oracle作为数据库，我们有两个模式，对于每个模式，我们在连接池中创建saprate连接。
如果我们一次从客户端发出最多 2 个请求来获取表中的数据，那么它工作正常，但每三次都会收到 java.sql.SQLException: ORA-00942: 表或 View 不存在 异常。
我想了解为什么会发生这种情况以及可能的原因是什么？请帮助我。
完整堆栈跟踪:
java.sql.SQLException: ORA-00942: table or view does not exist
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:111)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:330)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:287)
at oracle.jdbc.driver.T4C8Oall.receive(T4C8Oall.java:742)
at oracle.jdbc.driver.T4CPreparedStatement.doOall8(T4CPreparedStatement.java:212)
at oracle.jdbc.driver.T4CPreparedStatement.executeForDescribe(T4CPreparedStatement.java:795)
at oracle.jdbc.driver.OracleStatement.executeMaybeDescribe(OracleStatement.java:1030)
at oracle.jdbc.driver.T4CPreparedStatement.executeMaybeDescribe(T4CPreparedStatement.java:835)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1123)
at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3284)
at oracle.jdbc.driver.OraclePreparedStatement.executeQuery(OraclePreparedStatement.java:3328)
at DLRecordSetSQL.DLRecordSetSQL.setRecordCount(DLRecordSetSQL.java:3622)
at DLRecordSetSQL.DLRecordSetSQL.open(DLRecordSetSQL.java:3124)
at DLRecordSetSQL.DLRecordSetSQL.open(DLRecordSetSQL.java:3207)
at com.utility.queryManager.util.MetadataManager.init(MetadataManager.java:79)
at com.utility.queryManager.util.MetadataManager.<init>(MetadataManager.java:65)
at com.utility.queryManager.processor.UtilityManagerRequestProcessor.selectCommandRequestProcessor(UtilityManagerRequestProcessor.java:187)
at com.utility.queryManager.processor.UtilityManagerRequestProcessor.UtilityRequestProcessor(UtilityManagerRequestProcessor.java:77)
at com.utility.queryManager.servlet.UtilityManagerServlet.doPost(UtilityManagerServlet.java:36)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:563)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:399)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:317)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:204)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:311)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
最佳答案
我认为您的数据库已耗尽可用连接。
您可以将初始池大小设置为 5，因为它默认为 0。
更多内容，您可以阅读本教程:Setting Connection Pool Properties in Oracle
如Avi stated问题如下
Oracle database connections are not multi-threaded. If two or more threads simultaneously try to access the same connection, one of them will block until the other one finishes interacting with the connection.
So I guess you should try to verify whether your code exhibits this behaviour trying to access the same database connection from multiple threads at the same time.
关于java.sql.SQLException : ORA-00942: table or view does not exist, 每三次命中数据库一次，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/38910801/