相关疑难解决方法(0)

我真的想知道更多有关更新,导出和可以提供给hibernate.hbm2ddl.auto
我需要知道何时使用更新的值的更多信息,何时不知道？还有什么选择？

这些是可能发生在DB上的变化:

• 新表
• 旧表中的新列
• 列已删除
• 列的数据类型已更改
• 列的类型更改了其属性
• 桌子掉了
• 列的值已更改

在每种情况下,最佳解决方案是什么？

我正在发展springboot-springsession-jdbc-demo.当我只是运行代码时,我得到以下错误.它看起来我需要设置一些属性application.properties,以便事先创建模式/表.必需的配置已经放置,但仍然会出错.该代码存在于https://github.com/sivaprasadreddy/spring-session-samples中

参考错误:

org.springframework.jdbc.BadSqlGrammarException: PreparedStatementCallback; bad SQL grammar [DELETE FROM SPRING_SESSION WHERE LAST_ACCESS_TIME < ?]; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'test.spring_session' doesn't exist
    at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:231) ~[spring-jdbc-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73) ~[spring-jdbc-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:649) ~[spring-jdbc-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:870) ~[spring-jdbc-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:931) ~[spring-jdbc-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:941) ~[spring-jdbc-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.session.jdbc.JdbcOperationsSessionRepository$6.doInTransaction(JdbcOperationsSessionRepository.java:481) ~[spring-session-1.2.1.RELEASE.jar:na]
    at org.springframework.session.jdbc.JdbcOperationsSessionRepository$6.doInTransaction(JdbcOperationsSessionRepository.java:478) ~[spring-session-1.2.1.RELEASE.jar:na]
    at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133) ~[spring-tx-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.session.jdbc.JdbcOperationsSessionRepository.cleanUpExpiredSessions(JdbcOperationsSessionRepository.java:478) ~[spring-session-1.2.1.RELEASE.jar:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_45]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_45]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_45]
    at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_45]
    at org.springframework.scheduling.support.ScheduledMethodRunnable.run(ScheduledMethodRunnable.java:65) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.scheduling.concurrent.ReschedulingRunnable.run(ReschedulingRunnable.java:81) [spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at …