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java执行EXP导出Oracle数据库并没有导出的文件生成_course

#### java执行EXP导出Oracle数据库并没有导出的文件生成 在网上搜了很多方法都没有解决 ```java public static boolean EXP() { Runtime rt = Runtime.getRuntime(); try { Process p = rt.exec("cmd.exe EXP u/p@db..com:1521/ORCL FILE =D:\\ORACLE\\daochu.dmp tables=(AS_14)"); InputStream inputStream = p.getInputStream(); InputStream errorStream = p.getErrorStream(); writeToLocal("D:\\ORACLE\\zhengque.txt", inputStream); inputStream.close(); writeToLocal("D:\\ORACLE\\cuowu.txt", errorStream); errorStream.close(); } catch (IOException e) { e.printStackTrace(); } return false; } private static void writeToLocal(String destination, InputStream input) throws IOException { int index; byte[] bytes = new byte[1024]; FileOutputStream downloadFile = new FileOutputStream(destination); while ((index = input.read(bytes)) != -1) { downloadFile.write(bytes, 0, index); downloadFile.flush(); } downloadFile.close(); input.close(); return; } ```

java oracle读取数据中的图片_course

数据库存入了人员照片数据，查询人员信息table，并且显示照片列表，不知道java怎么处理多图从数据库读取显示。

java查询ORACLE数据乱码不能转码问题????_course

oracle字符集是US7的,java查询出的中文是乱码,用new String(rs.getString("name").getBytes("iso8859-1"), "GBK");无法转换,显示的还是乱码??????这个怎么回事啊????

java代码实现mysql到oracle的数据迁移，每天凌晨两点更新当天数据到oracle数据库_course

oracle数据库中的表是我根据需求自己建的，有八九张，并且oracle数据库中的那几张表，每张表对应的是mysql数据 库中两三张表里的部分字段，我要把做的就是把mysql中的数据导入到oracle数据库中，并且每天凌晨2点定时更新mysql中的当天数据到oracle数据库中。。做过的好心大哥大姐帮帮小弟啊，分享下代码，谢谢谢谢~~~~~~（java代码实现。。）

JDBC 连接java和Oracle 数据库 删除之后数据仍然存在_course

各位，我在Oracle数据库里面删除一条数据，之后在Java里面查询这条数据，结果显示还是存在这条数据，这是为什么？ 这是jdbc连接的代码： public class DbTools { Connection connection; public Connection getConn() { try{ //load the driver Class.forName("oracle.jdbc.driver.OracleDriver"); String url = "jdbc:oracle:thin:@localhost:1521:orcl"; String userName = "system"; String password = "123"; //get the connection object connection = DriverManager.getConnection(url, userName, password); }catch (ClassNotFoundException e){ e.printStackTrace(); }catch (SQLException e){ e.printStackTrace(); } return connection; } } ``` 表名：useinfo 1.usename 2.password 我在数据库里面先删除“22222”这条数据：  我再在java里面查询这条数据： public static void searchJDBC(String name){ String sql = String.format("select * from useinfo where username='%s'", name); DbTools dbTools = new DbTools(); Connection connection = dbTools.getConn(); try{ //create the statement object Statement statement=connection.createStatement(); ResultSet resultSet = statement.executeQuery(sql); while(resultSet.next()) { System.out.println(resultSet.getString("username")+ " "+ resultSet.getString("password")); } }catch (SQLException e){ e.printStackTrace(); } } ``` ``` 结果显示这条数据还是存在的 请问是什么原因？

java jdbc oracle相关问题_course

__java小白求各位大神一个问题： 我们在做一个java基础的小项目，主要做医院住院病人管理系统，基础有三张表，分别是病人表，医生表，医院部门表。在此基础上已经做好了相关的增删改查的功能。但是我们原有的构思是每往病人表里面添加一个病人通过java语言给这个病人创建一个详细住院日志表，包括他的每日花费，医生的查看信息等。这些功能都已经完成，但是在给老师看项目的时候，老师认为我们这种每次添加一个病人就创建一个表在数据库里面占的太大，说若果有两万个病人难道你创建两万个表？但是我最初的构思就是每个病人住院都应该有一个详细信息表（相当于日志表）在里面可以更新，我觉得挺符合实际的。在此我想知道，数据库建表真的有那么占空间吗？小白认为一张表而已，不会占据很大的空间，我想知道这些内容，但是百度也没有，希望各位大神能体会初学者做一个项目的艰辛，我真的不想改，如果占空间不大，我明天打算以此来说服老师，希望各位前辈解答。

Java 连 Oracle 数据库，捕获的异常怎么切换成英文版_course

如题： 现在捕获的异常是 ORA-00942: 表或视图不存在 怎么改成 ORA-00942: table or view does not exist 是在哪里改配置。有大神指点下呗

java多线程高并发下的oracle数据库异常_course

代码的功能是生成一个随机的序列化的订单号，正常的情况下一个一个跑没问题，在进行压力测试的时候，多线程高并发下，oracle的create语句就会报错，说是 java.lang.RuntimeException: org.springframework.jdbc.BadSqlGrammarException: ConnectionCallback; bad SQL grammar []; nested exception is java.sqlSQLException: ORA-00955: 名称已由现有对象使用 求大神看下。 代码如下： ``` package utils.spring; import org.springframework.beans.factory.InitializingBean; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.dao.DataAccessException; import org.springframework.jdbc.core.ConnectionCallback; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.jdbc.core.PreparedStatementCallback; import org.springframework.stereotype.Component; import org.springframework.transaction.PlatformTransactionManager; import org.springframework.transaction.TransactionStatus; import org.springframework.transaction.support.TransactionCallback; import org.springframework.transaction.support.TransactionTemplate; import utils.Lang; import javax.sql.DataSource; import java.sql.*; import java.util.Map; import java.util.concurrent.ConcurrentHashMap; /** * 序列发生器（可用于高并发、可回收等场景） * * @author lujijiang * */ @Component @ConfigurationProperties(prefix = "seqGenerator") final public class SequenceGenerator implements InitializingBean { interface Atom<T> { T atom(Connection connection) throws Exception; } public static <T> T atom(Connection connection, Atom<T> atom) throws Exception { connection.setAutoCommit(false); connection .setTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED); try { T obj = atom.atom(connection); connection.commit(); return obj; } catch (Exception e) { connection.rollback(); throw e; } } static Map<String, String> createSqlMap = new ConcurrentHashMap<String, String>(); static { createSqlMap .put("h2", "CREATE TABLE %s (v$key BIGINT NOT NULL,v$key$ varchar(256),v$seq BIGINT NOT NULL,v$state CHAR(1) NOT NULL, PRIMARY KEY (v$key,v$seq))"); createSqlMap .put("mysql", "CREATE TABLE %s (v$key BIGINT NOT NULL,v$key$ varchar(256),v$seq BIGINT NOT NULL,v$state CHAR(1) NOT NULL, PRIMARY KEY (v$key,v$seq))"); createSqlMap .put("informix", "CREATE TABLE %s (v$key DECIMAL(16,0) NOT NULL,v$key$ varchar(256),v$seq DECIMAL(16,0) NOT NULL,v$state CHAR(1) NOT NULL, PRIMARY KEY (v$key,v$seq))"); createSqlMap .put("oracle", "CREATE TABLE %s (v$key NUMBER(16,0) NOT NULL,v$key$ varchar2(256),v$seq NUMBER(16,0) NOT NULL,v$state CHAR(1) NOT NULL, PRIMARY KEY (v$key,v$seq))"); } static Map<String, String> insertSqlMap = new ConcurrentHashMap<String, String>(); static { insertSqlMap .put("h2", "insert into %s(v$key,v$key$,v$seq,v$state) values(%d,'%s',(select ifnull(max(t.v$seq),%d)+%d from %s t where t.v$key=%d),'1')"); insertSqlMap .put("mysql", "insert into %s(v$key,v$key$,v$seq,v$state) values(%d,'%s',(select ifnull(max(t.v$seq),%d)+%d from %s t where t.v$key=%d),'1')"); insertSqlMap .put("informix", "insert into %s(v$key,v$key$,v$seq,v$state) values(%d,'%s',(select nvl(max(t.v$seq),%d)+%d from %s t where t.v$key=%d),'1')"); insertSqlMap .put("oracle", "insert into %s(v$key,v$key$,v$seq,v$state) values(%d,'%s',(select nvl(max(t.v$seq),%d)+%d from %s t where t.v$key=%d),'1')"); } /** * 事务模版 */ TransactionTemplate transactionTemplate; /** * 是否使用新事务 */ boolean newTransaction = true; /** * JDBC模版 */ JdbcTemplate jdbcTemplate; /** * 尝试次数（默认10次） */ int tryTime = 10; /** * 数据库类型 */ String databaseType; /** * 表名 */ private String tableName; /** * 容量 */ private int capacity = 25; /** * 步进 */ private int step = 1; /** * 是否可回收序列号 */ protected boolean recyclable; @Autowired public void setTransactionManager( PlatformTransactionManager transactionManager) { if (transactionManager != null) { transactionTemplate = new TransactionTemplate(transactionManager); transactionTemplate .setIsolationLevel(TransactionTemplate.ISOLATION_READ_COMMITTED); transactionTemplate .setPropagationBehavior(TransactionTemplate.PROPAGATION_REQUIRED); } } public boolean isNewTransaction() { return newTransaction; } public void setNewTransaction(boolean newTransaction) { this.newTransaction = newTransaction; } public TransactionTemplate getTransactionTemplate() { return transactionTemplate; } public void setJdbcTemplate(JdbcTemplate jdbcTemplate) { this.jdbcTemplate = jdbcTemplate; } @Autowired public void setDataSource(DataSource dataSource) { if (jdbcTemplate == null) { jdbcTemplate = new JdbcTemplate(dataSource); } } public void setTransactionTemplate(TransactionTemplate transactionTemplate) { this.transactionTemplate = transactionTemplate; } public void setTryTime(int tryTime) { this.tryTime = tryTime; } public void setDatabaseType(String databaseType) { if (databaseType != null) { databaseType = databaseType.trim().toLowerCase(); this.databaseType = databaseType; } } public void setTableName(String tableName) { this.tableName = tableName == null ? null : tableName.trim(); } public void setCapacity(int capacity) { this.capacity = capacity; } public void setStep(int step) { this.step = step < 1 ? 1 : step; } public void setRecyclable(boolean recyclable) { this.recyclable = recyclable; } /** * 创建序列 * * @param name * @param length * @param start * @return */ public String generateSequence(String name, int length, long start) { final long key = generateKey(name); try { return generateSequence(key, length, start, name); } catch (Throwable t) { createSequenceTable();//错误就是定位在这里 int time = tryTime >= 0 ? tryTime : 10000; while (time-- > 0) { try { return generateSequence(key, length, start, name); } catch (Throwable e) { } } throw new RuntimeException("Generate sequence failure", t); } } private long generateKey(String name) { return 10000000000L + name.trim().hashCode(); } /** * 创建序列 * * @param key * @param length * @return */ public String generateSequence(String key, int length) { return generateSequence(key, length, 0); } /** * 创建序列 * * @param key * @return */ public String generateSequence(String key) { return generateSequence(key, 6); } private synchronized void createSequenceTable() { try { jdbcTemplate.execute(new ConnectionCallback<Integer>() { public Integer doInConnection(Connection connection) throws SQLException, DataAccessException { ResultSet rs = connection.getMetaData().getTables(null, null, tableName, null); try { while (rs.next()) { return 1; } } finally { rs.close(); } String createSql = String.format( createSqlMap.get(databaseType), tableName); Statement statement = connection.createStatement(); try { statement.execute(createSql);//错误就是定位在这里 } finally { statement.close(); } return 0; } }); } catch (Throwable t) { throw new RuntimeException(t); } } private String generateSequence(final long key, final int length, final long start, final String name) { if (newTransaction) { try { Connection connection = jdbcTemplate.getDataSource() .getConnection(); try { return atom(connection, new Atom<String>() { @Override public String atom(Connection connection) throws Exception { if (recyclable) { String no = getRecoveredSequence(connection, key, length); if (no != null) { return no; } } Statement statement = connection.createStatement(); try { String insertSql = String.format(insertSqlMap .get(databaseType), tableName, key, name.replace("'", "''"), start < 0 ? 0 : start, step, tableName, key); execute(connection, insertSql); String querySql = String .format("select max(v$seq) from %s where v$key=%d and v$state='1'", tableName, key); ResultSet rs = statement.executeQuery(querySql); try { while (rs.next()) { Long max = rs.getLong(1); if (max < start) {// 重新初始化 String deleteSql = String .format("delete from %s where v$key=%d and v$state='1'", tableName, key); execute(connection, deleteSql); insertSql = String.format( insertSqlMap .get(databaseType), tableName, key, name.replace("'", "''"), start < 0 ? 0 : start, step, tableName, key); execute(connection, insertSql); return fillLeftZero(start, length); } if (capacity > 0 && max % capacity == 0) { String deleteSql = String .format("delete from %s where v$key=%d and v$seq<>%d and v$state='1'", tableName, key, max); execute(connection, deleteSql); } return fillLeftZero(max, length); } } finally { rs.close(); } } finally { statement.close(); } throw new IllegalStateException( SequenceGenerator.this.getClass() .getSimpleName() + "无法获取单号，不可能发生的异常"); } }); } finally { connection.close(); } } catch (Exception e) { throw Lang.unchecked(e); } } return getTransactionTemplate().execute( new TransactionCallback<String>() { public String doInTransaction(TransactionStatus ts) { try { if (recyclable) { String no = jdbcTemplate .execute(new ConnectionCallback<String>() { public String doInConnection( Connection connection) throws SQLException, DataAccessException { return getRecoveredSequence( connection, key, length); } }); if (no != null) { return no; } } String insertSql = String.format(insertSqlMap .get(databaseType), tableName, key, name .replace("'", "''"), start < 0 ? 0 : start, step, tableName, key); execute(insertSql); String querySql = String .format("select max(v$seq) from %s where v$key=%d and v$state='1'", tableName, key); Long max = jdbcTemplate.queryForObject(querySql, Long.class); if (max < start) {// 重新初始化 String deleteSql = String .format("delete from %s where v$key=%d and v$state='1'", tableName, key); execute(deleteSql); insertSql = String.format(insertSqlMap .get(databaseType), tableName, key, name.replace("'", "''"), start < 0 ? 0 : start, step, tableName, key); execute(insertSql); return fillLeftZero(start, length); } if (capacity > 0 && max % capacity == 0) { String deleteSql = String .format("delete from %s where v$key=%d and v$seq<>%d and v$state='1'", tableName, key, max); execute(deleteSql); } return fillLeftZero(max, length); } catch (Throwable t) { ts.isRollbackOnly(); throw new RuntimeException(t); } } }); } /** * 参数化执行SQL * * @param sql * @param args * @return */ protected int execute(String sql, final Object... args) { return jdbcTemplate.execute(sql, new PreparedStatementCallback<Integer>() { public Integer doInPreparedStatement(PreparedStatement ps) throws SQLException, DataAccessException { if (args != null) { for (int i = 0; i < args.length; i++) { ps.setObject(i + 1, args[i]); } } return ps.executeUpdate(); } }); } /** * 参数化执行SQL * * @param sql * @param args * @return * @throws SQLException */ protected int execute(Connection conn, String sql, final Object... args) throws SQLException { PreparedStatement ps = conn.prepareStatement(sql); try { if (args != null) { for (int i = 0; i < args.length; i++) { ps.setObject(i + 1, args[i]); } } return ps.executeUpdate(); } finally { ps.close(); } } protected String fillLeftZero(Long max, int length) { StringBuilder sb = new StringBuilder(); sb.append(max); if (sb.length() >= length) { return sb.substring(sb.length() - length); } else { for (int i = sb.length(); i < length; i++) { sb.insert(0, '0'); } } return sb.toString(); } /** * 获取已回收的序列 * * @param connection * @param key * @throws SQLException */ protected String getRecoveredSequence(Connection connection, long key, int length) throws SQLException { Statement statement = connection.createStatement( ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE); try { String querySql = String .format("select v$key,v$seq,v$state from %s where v$key = %d and v$state<>'1' for update", tableName, key); statement.executeQuery(querySql); querySql = String .format("select v$key,v$seq,v$state from %s where v$key = %d and v$state<>'1' order by v$seq asc", tableName, key); ResultSet rs = statement.executeQuery(querySql); try { while (rs.next()) { try { Long min = rs.getLong(2); rs.updateString(3, "1"); rs.updateRow(); return fillLeftZero(min, length); } catch (Throwable ex) { } } } finally { rs.close(); } } finally { statement.close(); } return null; } /** * 回收序列号 * * @param name * @param sequence */ public void recoveredSequence(final String name, final String sequence) { final long key = generateKey(name); final long seq = Long.valueOf(sequence); if (newTransaction) { try { Connection connection = jdbcTemplate.getDataSource() .getConnection(); try { atom(connection, new Atom<Object>() { public Object atom(Connection connection) throws Exception { String updateSql = String .format("update %s set v$state='0' where v$key=%d and v$seq=%d", tableName, key, seq); int count = execute(connection, updateSql); if (count == 0) { String insertSql = String .format("insert into %s(v$key,v$key$,v$seq,v$state) values(%d,'%s',%d,'0')", tableName, key, name.replace("'", "''"), seq); execute(connection, insertSql); } return null; } }); connection.commit(); } finally { connection.close(); } } catch (Exception e) { throw Lang.unchecked(e); } } else { transactionTemplate.execute(new TransactionCallback<Integer>() { public Integer doInTransaction(TransactionStatus status) { try { String updateSql = String .format("update %s set v$state='0' where v$key=%d and v$seq=%d", tableName, key, seq); int count = execute(updateSql); if (count == 0) { String insertSql = String .format("insert into %s(v$key,v$key$,v$seq,v$state) values(%d,'%s',%d,'0')", tableName, key, name.replace("'", "''"), seq); execute(insertSql); } return null; } catch (Throwable t) { status.isRollbackOnly(); throw new RuntimeException(t); } } }); } } public void afterPropertiesSet() throws Exception { if (this.databaseType == null) { throw new IllegalArgumentException(String.format( "Property '%s' is required", "databaseType")); } if (databaseType != null) { if (!createSqlMap.containsKey(databaseType)) { throw new IllegalStateException(String.format( "Unsupported database type:%s", databaseType)); } } if (this.jdbcTemplate == null) { throw new IllegalArgumentException(String.format( "Property '%s' or '%s' is required", "dataSource", "jdbcTemplate")); } if (this.tableName == null) { throw new IllegalArgumentException(String.format( "Property '%s' is required", "tableName")); } if (!tableName.matches("[a-zA-Z_][a-zA-Z0-9_]*") || tableName.length() > 16) { throw new IllegalStateException(String.format( "Illegal tableName:%s", tableName)); } if (!this.newTransaction) { if (this.transactionTemplate == null) { throw new IllegalArgumentException(String.format( "Property '%s' is required", "transactionManager")); } } } } ``` java.lang.RuntimeException: org.springframework.jdbc.BadSqlGrammarException: ConnectionCallback; bad SQL grammar []; nested exception is java.sql.SQLException: ORA-00955: 名称已由现有对象使用 at utils.spring.SequenceGenerator.createSequenceTable(SequenceGenerator.java:272) at utils.spring.SequenceGenerator.generateSequence(SequenceGenerator.java:202) at utils.spring.SequenceGenerator.generateSequence(SequenceGenerator.java:227) at cart.service.service.OrderService.generateOrderNo(OrderService.java:806) at cart.service.service.OrderService.saveVirtualGoodsToOrder(OrderService.java:220) at cart.service.service.OrderService$$FastClassBySpringCGLIB$$19f99be7.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:720) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:655) at cart.service.service.OrderService$$EnhancerBySpringCGLIB$$feb8eef.saveVirtualGoodsToOrder(<generated>) at cart.service.apiImpl.OrderMainApiImpl.saveVirtualGoodsToOrder(OrderMainApiImpl.java:223) at cart.service.apiImpl.OrderMainApiImpl$$FastClassBySpringCGLIB$$fa3518e.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:651) at cart.service.apiImpl.OrderMainApiImpl$$EnhancerBySpringCGLIB$$497f044.saveVirtualGoodsToOrder(<generated>) 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 com.weibo.api.motan.rpc.DefaultProvider.invoke(DefaultProvider.java:57) at com.weibo.api.motan.rpc.AbstractProvider.call(AbstractProvider.java:47) at com.weibo.api.motan.filter.AccessLogFilter.filter(AccessLogFilter.java:56) at com.weibo.api.motan.protocol.support.ProtocolFilterDecorator$2.call(ProtocolFilterDecorator.java:150) at utils.rpc.motan.filter.OpenEntityManagerInMotanFilter.filter(OpenEntityManagerInMotanFilter.java:171) at com.weibo.api.motan.protocol.support.ProtocolFilterDecorator$2.call(ProtocolFilterDecorator.java:150) at com.weibo.api.motan.transport.ProviderMessageRouter.call(ProviderMessageRouter.java:96) at com.weibo.api.motan.transport.ProviderProtectedMessageRouter.call(ProviderProtectedMessageRouter.java:79) at com.weibo.api.motan.transport.ProviderMessageRouter.handle(ProviderMessageRouter.java:91) at com.weibo.api.motan.transport.support.DefaultRpcHeartbeatFactory$HeartMessageHandleWrapper.handle(DefaultRpcHeartbeatFactory.java:82) at com.weibo.api.motan.transport.netty.NettyChannelHandler.processRequest(NettyChannelHandler.java:139) at com.weibo.api.motan.transport.netty.NettyChannelHandler.access$000(NettyChannelHandler.java:47) at com.weibo.api.motan.transport.netty.NettyChannelHandler$1.run(NettyChannelHandler.java:116) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Caused by: org.springframework.jdbc.BadSqlGrammarException: ConnectionCallback; bad SQL grammar []; nested exception is java.sql.SQLException: ORA-00955: 名称已由现有对象使用 at org.springframework.jdbc.support.SQLStateSQLExceptionTranslator.doTranslate(SQLStateSQLExceptionTranslator.java:99) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:81) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:81) at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:360) at utils.spring.SequenceGenerator.createSequenceTable(SequenceGenerator.java:247) ... 39 more Caused by: java.sql.SQLException: ORA-00955: 名称已由现有对象使用 at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112) at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:331) at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:288) at oracle.jdbc.driver.T4C8Oall.receive(T4C8Oall.java:745) at oracle.jdbc.driver.T4CStatement.doOall8(T4CStatement.java:210) at oracle.jdbc.driver.T4CStatement.executeForRows(T4CStatement.java:961) at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1190) at oracle.jdbc.driver.OracleStatement.executeInternal(OracleStatement.java:1726) at oracle.jdbc.driver.OracleStatement.execute(OracleStatement.java:1696) at utils.spring.SequenceGenerator$1.doInConnection(SequenceGenerator.java:264) at utils.spring.SequenceGenerator$1.doInConnection(SequenceGenerator.java:247) at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:353) ... 40 more

【求助】java使用jdbc连接Oracle 11g ex版本数据库时的问题_course

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