java - SQL - java中的转义字符

Question

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已关闭 11 年前。

我正在尝试在 Java 中运行此 SQL 语句

 public void updateDBSettings() throws SQLException {


        //here the values from the updatedSettingsMap will be inserted into the database

            String storedPassword = null;        
            String SQL_Statement = null;

            if (ds == null) throw new SQLException();      
       Connection conn = ds.getConnection();
            if (conn == null) throw new SQLException();      

       try {
            conn.setAutoCommit(false);
            boolean committed = false;
                try {
                       SQL_Statement = "UPDATE GLOBALSETTINGS" +
                                            "SET \"SettingValue\"  =" +
                                              "CASE" +
                                                "WHEN \"SettingName\" = 'SessionTTL' THEN '2'" +
                                                "WHEN \"SettingName\" = 'MaxUsersActive' THEN '23'" +
                                              "END" +
                                       "WHERE \"SettingName\"  IN ('SessionTTL', 'MaxUsersActive')";


                       PreparedStatement updateQuery = conn.prepareStatement(SQL_Statement);
  //                     updateQuery.setString(1, "20");
  //                     updateQuery.setString(2, "40");

                       updateQuery.executeQuery();

                       conn.commit();
                       committed = true;
                 } finally {
                       if (!committed) conn.rollback();
                       }
            }
                finally {               
                conn.close();

                }  

       }    

当我将其部署在 Glassfish 上并运行它时，我收到此错误堆栈

javax.faces.el.E​​valuationException:java.sql.SQLSyntaxErrorException:ORA-00971:缺少 SET 关键字

at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:102)
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
at javax.faces.component.UICommand.broadcast(UICommand.java:315)
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1542)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:849)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:746)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1045)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:228)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:722)

由以下原因引起:java.sql.SQLSyntaxErrorException:ORA-00971:缺少 SET 关键字

at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:445)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:396)
at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:879)
at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:450)
at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:192)
at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:531)
at oracle.jdbc.driver.T4CPreparedStatement.doOall8(T4CPreparedStatement.java:207)
at oracle.jdbc.driver.T4CPreparedStatement.executeForRows(T4CPreparedStatement.java:1044)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1329)
at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3584)
at oracle.jdbc.driver.OraclePreparedStatement.executeQuery(OraclePreparedStatement.java:3628)
at oracle.jdbc.driver.OraclePreparedStatementWrapper.executeQuery(OraclePreparedStatementWrapper.java:1493)
at com.sun.gjc.spi.jdbc40.PreparedStatementWrapper40.executeQuery(PreparedStatementWrapper40.java:642)
at com.DX_57.SM_57.Application.updateDBSettings(Application.java:131)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at javax.el.BeanELResolver.invokeMethod(BeanELResolver.java:779)
at javax.el.BeanELResolver.invoke(BeanELResolver.java:528)
at javax.el.CompositeELResolver.invoke(CompositeELResolver.java:257)
at com.sun.el.parser.AstValue.invoke(AstValue.java:248)
at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:302)
at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105)
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
... 32 more

如果我在 SQL Developer 中运行此 SQL 查询，它工作正常:

UPDATE GLOBALSETTINGS
SET "SettingValue" =
  CASE
    WHEN "SettingName" = 'SessionTTL'
    THEN '30'
    WHEN "SettingName" = 'MaxUsersActive'
    THEN '40'
  END
WHERE "SettingName" IN ('SessionTTL', 'MaxUsersActive');

我添加了转义字符，以便在 java 中使用 SQL 语句。我需要在单引号前放置转义字符吗？

    SQL_Statement = "UPDATE GLOBALSETTINGS" +
            "SET \"SettingValue\"  =" +
              "CASE" +
                "WHEN \"SettingName\" = 'SessionTTL' THEN '2'" +
                "WHEN \"SettingName\" = 'MaxUsersActive' THEN '23'" +
              "END" +
       "WHERE \"SettingName\"  IN ('SessionTTL', 'MaxUsersActive')";

Answer 1

连接语句中的 GLOBALSETTINGS 和 SET 之间没有空格，因此该语句不是有效的 SQL。您对 When、End 和Where 关键字也有同样的问题。