使用Oracle数据库运行，启动报错。

[bes2008]

Describe the bug
使用Oracle数据库运行，启动报错。
报错内容：
2024-08-30 17:15:12,901 WARN HikariPool-1 - Connection oracle.jdbc.driver.T4CConnection@4653747d marked as broken because of SQLSTATE(0A000), ErrorCode(304 7)

java.sql.SQLException: ORA-03047: number '1' is not syntactically valid following '...1 FROM config_info_tag LIMIT '

https://docs.oracle.com/error-help/db/ora-03047/
at oracle.jdbc.driver.T4CTTIoer11.processError(T4CTTIoer11.java:709)
at oracle.jdbc.driver.T4CTTIoer11.processError(T4CTTIoer11.java:609)
at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:1290)
at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:1100)
at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:408)
at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:483)
at oracle.jdbc.driver.T4CStatement.doOall8(T4CStatement.java:170)
at oracle.jdbc.driver.T4CStatement.executeForDescribe(T4CStatement.java:1029)
at oracle.jdbc.driver.OracleStatement.prepareDefineBufferAndExecute(OracleStatement.java:1299)
at oracle.jdbc.driver.OracleStatement.executeMaybeDescribe(OracleStatement.java:1224)
at oracle.jdbc.driver.OracleStatement.executeSQLSelect(OracleStatement.java:1592)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1442)
at oracle.jdbc.driver.OracleStatement.executeQuery(OracleStatement.java:1858)
at oracle.jdbc.driver.OracleStatementWrapper.executeQuery(OracleStatementWrapper.java:382)
at com.zaxxer.hikari.pool.ProxyStatement.executeQuery(ProxyStatement.java:111)
at com.zaxxer.hikari.pool.HikariProxyStatement.executeQuery(HikariProxyStatement.java)
at org.springframework.jdbc.core.JdbcTemplate$1QueryStatementCallback.doInStatement(JdbcTemplate.java:453)
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:383)
at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:466)
at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:476)
at org.springframework.jdbc.core.JdbcTemplate.queryForObject(JdbcTemplate.java:509)
at org.springframework.jdbc.core.JdbcTemplate.queryForObject(JdbcTemplate.java:516)
at com.alibaba.nacos.core.namespace.repository.ExternalNamespacePersistServiceImpl.isExistTable(ExternalNamespacePersistServiceImpl.java:165)
at com.alibaba.nacos.config.server.service.dump.DumpService.dumpOperate(DumpService.java:274)
at com.alibaba.nacos.config.server.service.dump.ExternalDumpService.init(ExternalDumpService.java:65)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcess or.java:389)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBea nPostProcessor.java:333)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPos tProcessor.java:157)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapable BeanFactory.java:440)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1796)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:620)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:336)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:334)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:209)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1391)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1311)
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:904)
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:781)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:220)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1372)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1222)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:336)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:334)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:209)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:955)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:591)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:147)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:732)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:409)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:308)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1300)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1289)
at com.alibaba.nacos.Nacos.main(Nacos.java:46)
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 org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:49)
at org.springframework.boot.loader.Launcher.launch(Launcher.java:108)
at org.springframework.boot.loader.Launcher.launch(Launcher.java:58)
at org.springframework.boot.loader.PropertiesLauncher.main(PropertiesLauncher.java:467)
Caused by: oracle.jdbc.OracleDatabaseException: ORA-03047: number '1' is not syntactically valid following '...1 FROM config_info_tag LIMIT '

    at oracle.jdbc.driver.T4CTTIoer11.processError(T4CTTIoer11.java:717)
    ... 71 common frames omitted

Expected behavior

期望在启动时，nacos.log 中无异常

Actually behavior
报错会发生在 查询表 config_info_tag, config_info_beta 是否存在时，

How to Reproduce
Steps to reproduce the behavior:

1. 添加Oracle JDBC驱动到 nacos/plugins目录
2. 准备好Oracle数据库，表
3. 在application.properties配置好 Oracle连接
4. 启动Nacos 单机模式
5. 查看nacos.log文件

问题原因

Oracle中分页不支持 Limit关键字，而在 ExternalNamespacePersistServiceImpl#isExistTable 方法中，查询指定表是否存在时，使用了limit关键字，是写死了的。没有通过插件的方式让自定义。

[huangkemingyyds]

https://github.com/nacos-group/nacos-plugin/tree/develop/nacos-datasource-plugin-ext/nacos-oracle-datasource-plugin-ext

使用可以使用社区提供的插件。

[bes2008]

@huangkemingyyds 根本就不是插件的问题

[huangkemingyyds]

@i will solve it@

[KomachiSion]

有不同方言的情况下， 最好是抽到插件去实现。不然怎么改都有可能有不支持的SQL和数据源

[bes2008]

常规方案，应该是提到插件中不同方言来实现。
如果能够通过一个SQL可以完成，更好。

[huangkemingyyds]

我也思考过这个问题，就目前来说，在工程代码中目前还是存在声明式sql, 并没有完全通过插件实现。
我想的是先对bug 进行修复，后续再新增feat ,并对不同的插件进行补充。这样影响是最小的。

[bes2008]

可以尝试使用 JDBC API： DatabaseMetaData.getTables() 来完成
这样就不需要直接使用SQL了，也就不需要处理不同数据库的不同。

但是这有个前提，数据库的JDBC驱动，都实现了这个方法