（Spring Batch）为啥表'batch_job_instance'已经存在？

Posted 2023-02-27

【中文标题】（Spring Batch）为啥表\'batch_job_instance\'已经存在？

【英文标题】：(Spring Batch) Why Table 'batch_job_instance' already exists?（Spring Batch）为什么表'batch_job_instance'已经存在？

【发布时间】：2021-08-12 05:12:17

【问题描述】：

我是 Spring Batch 的新手，刚刚在 Spring Batch 中运行我的第一个项目。

但是当我在 Spring Batch 中配置数据库时，它会抛出错误。

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2021-05-23 13:29:58.390 ERROR 19733 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSourceScriptDatabaseInitializer' defined in class path resource [org/springframework/boot/autoconfigure/sql/init/DataSourceInitializationConfiguration.class]: Invocation of init method failed; nested exception is org.springframework.jdbc.datasource.init.ScriptStatementFailedException: Failed to execute SQL script statement #1 of class path resource [org/springframework/batch/core/schema-mysql.sql]: CREATE TABLE BATCH_JOB_INSTANCE ( JOB_INSTANCE_ID BIGINT NOT NULL PRIMARY KEY , VERSION BIGINT , JOB_NAME VARCHAR(100) NOT NULL, JOB_KEY VARCHAR(32) NOT NULL, constraint JOB_INST_UN unique (JOB_NAME, JOB_KEY) ) ENGINE=InnoDB; nested exception is java.sql.SQLSyntaxErrorException: Table 'batch_job_instance' already exists
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1786) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:602) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:524) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:322) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:944) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918) ~[spring-context-5.3.7.jar:5.3.7]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) ~[spring-context-5.3.7.jar:5.3.7]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:758) [spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:438) [spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:337) [spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1336) [spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1325) [spring-boot-2.5.0.jar:2.5.0]
    at com.example.demo.DemoApplication.main(DemoApplication.java:10) [classes/:na]
Caused by: org.springframework.jdbc.datasource.init.ScriptStatementFailedException: Failed to execute SQL script statement #1 of class path resource [org/springframework/batch/core/schema-mysql.sql]: CREATE TABLE BATCH_JOB_INSTANCE ( JOB_INSTANCE_ID BIGINT NOT NULL PRIMARY KEY , VERSION BIGINT , JOB_NAME VARCHAR(100) NOT NULL, JOB_KEY VARCHAR(32) NOT NULL, constraint JOB_INST_UN unique (JOB_NAME, JOB_KEY) ) ENGINE=InnoDB; nested exception is java.sql.SQLSyntaxErrorException: Table 'batch_job_instance' already exists
    at org.springframework.jdbc.datasource.init.ScriptUtils.executeSqlScript(ScriptUtils.java:622) ~[spring-jdbc-5.3.7.jar:5.3.7]
    at org.springframework.jdbc.datasource.init.ResourceDatabasePopulator.populate(ResourceDatabasePopulator.java:254) ~[spring-jdbc-5.3.7.jar:5.3.7]
    at org.springframework.jdbc.datasource.init.DatabasePopulatorUtils.execute(DatabasePopulatorUtils.java:49) ~[spring-jdbc-5.3.7.jar:5.3.7]
    at org.springframework.boot.jdbc.init.DataSourceScriptDatabaseInitializer.runScripts(DataSourceScriptDatabaseInitializer.java:72) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.sql.init.AbstractScriptDatabaseInitializer.runScripts(AbstractScriptDatabaseInitializer.java:131) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.sql.init.AbstractScriptDatabaseInitializer.applyScripts(AbstractScriptDatabaseInitializer.java:91) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.sql.init.AbstractScriptDatabaseInitializer.applySchemaScripts(AbstractScriptDatabaseInitializer.java:81) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.sql.init.AbstractScriptDatabaseInitializer.initializeDatabase(AbstractScriptDatabaseInitializer.java:75) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.sql.init.AbstractScriptDatabaseInitializer.afterPropertiesSet(AbstractScriptDatabaseInitializer.java:65) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1845) ~[spring-beans-5.3.7.jar:5.3.7]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1782) ~[spring-beans-5.3.7.jar:5.3.7]
    ... 17 common frames omitted
Caused by: java.sql.SQLSyntaxErrorException: Table 'batch_job_instance' already exists
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:120) ~[mysql-connector-java-8.0.25.jar:8.0.25]
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122) ~[mysql-connector-java-8.0.25.jar:8.0.25]
    at com.mysql.cj.jdbc.StatementImpl.executeInternal(StatementImpl.java:762) ~[mysql-connector-java-8.0.25.jar:8.0.25]
    at com.mysql.cj.jdbc.StatementImpl.execute(StatementImpl.java:646) ~[mysql-connector-java-8.0.25.jar:8.0.25]
    at com.zaxxer.hikari.pool.ProxyStatement.execute(ProxyStatement.java:94) ~[HikariCP-4.0.3.jar:na]
    at com.zaxxer.hikari.pool.HikariProxyStatement.execute(HikariProxyStatement.java) ~[HikariCP-4.0.3.jar:na]
    at org.springframework.jdbc.datasource.init.ScriptUtils.executeSqlScript(ScriptUtils.java:601) ~[spring-jdbc-5.3.7.jar:5.3.7]
    ... 27 common frames omitted


Process finished with exit code 1

上面写着Table 'batch_job_instance' already exists，但我只是创建了一个新模式来运行这个项目。我不知道为什么它说已经存在。

这是我的数据源配置：

spring.datasource.url=jdbc:mysql://localhost:3306/springbatch
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driverClassName=com.mysql.cj.jdbc.Driver
spring.sql.init.schema-locations=classpath:/org/springframework/batch/core/schema-mysql.sql

spring.batch.jdbc.initialize-schema=always

我搜索了一些问题并遵循他们的建议，例如将 initialize-schema 更改为 never。但这无济于事。

有谁知道如何解决这个问题？非常感谢。

【问题讨论】：

即使在第一次运行时它也显示Table 'batch_job_instance' already exists存在？

【参考方案1】：

您应该在此之前手动创建表或执行一次应用程序。

由于您已设置spring.batch.jdbc.initialize-schema=always，因此您需要确保在运行您的应用程序之前删除所有批处理表，它应该可以按预期工作。