我有以下脚本来创建表 autolife.log:

CREATE TABLE `log` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `idpoint` int(11) NOT NULL,
  `value` varchar(10) NOT NULL,
  `time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`),
  KEY `fk_point_id` (`idpoint`),
  CONSTRAINT `fk_point_id` FOREIGN KEY (`idpoint`) REFERENCES `point` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=155562 DEFAULT CHARSET=latin2$$

所以我使用 JPA 工具 在 Eclipse Indigo 中从表创建实体:

@Entity
public class Log implements Serializable {
    private static final long serialVersionUID = 1L;

    @Id
    @SequenceGenerator(name="LOG_ID_GENERATOR", sequenceName="SEQUENCE_KEY")
    @GeneratedValue(strategy=GenerationType.SEQUENCE, generator="LOG_ID_GENERATOR")
    private Integer id;

    private Timestamp time;

    private String value;

    //bi-directional many-to-one association to Point
    @ManyToOne
    @JoinColumn(name="idpoint")
    private Point point;

    public Log() {
    }

    // get's and set's

当我在我的本地主机上运行时，工作正常，但是当我导出 .war 并投入生产时，给我这个错误(下面你可以看到代码生成的异常):

ubuntu@domU-12-31-39-0A-12-7B:~/glassfish/glassfish3/glassfish/domains/domain1/logs$ vi server.log
        at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:193)
        at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeSelectCall(DatasourceCallQueryMechanism.java:264)
        at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.selectAllRows(DatasourceCallQueryMechanism.java:646)
        at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRowsFromTable(ExpressionQueryMechanism.java:2611)
        at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRows(ExpressionQueryMechanism.java:2570)
        at org.eclipse.persistence.queries.ReadAllQuery.executeObjectLevelReadQuery(ReadAllQuery.java:420)
        at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1081)
        at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:844)
        at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1040)
        at org.eclipse.persistence.queries.ReadAllQuery.execute(ReadAllQuery.java:392)
        at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeInUnitOfWork(ObjectLevelReadQuery.java:1128)
        at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.internalExecuteQuery(UnitOfWorkImpl.java:2871)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1516)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1498)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1463)
        at org.eclipse.persistence.internal.jpa.EJBQueryImpl.executeReadQuery(EJBQueryImpl.java:485)
        at org.eclipse.persistence.internal.jpa.EJBQueryImpl.getResultList(EJBQueryImpl.java:742)
        at com.brainset.eao.LogEAO.list(LogEAO.java:54)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.glassfish.ejb.security.application.EJBSecurityManager.runMethod(EJBSecurityManager.java:1052)
        at org.glassfish.ejb.security.application.EJBSecurityManager.invoke(EJBSecurityManager.java:1124)
        at com.sun.ejb.containers.BaseContainer.invokeBeanMethod(BaseContainer.java:5388)
        at com.sun.ejb.EjbInvocation.invokeBeanMethod(EjbInvocation.java:619)
        at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:800)
        at com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:571)
        at com.sun.ejb.containers.interceptors.SystemInterceptorProxy.doAround(SystemInterceptorProxy.java:162)
        at com.sun.ejb.containers.interceptors.SystemInterceptorProxy.aroundInvoke(SystemInterceptorProxy.java:144)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:861)
        at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:800)
        at com.sun.ejb.containers.interceptors.InterceptorManager.intercept(InterceptorManager.java:370)
        at com.sun.ejb.containers.BaseContainer.__intercept(BaseContainer.java:5360)
        at com.sun.ejb.containers.BaseContainer.intercept(BaseContainer.java:5348)
        at com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:214)
        ... 44 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'autolife.LOG' doesn't exist
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
        at com.mysql.jdbc.Util.getInstance(Util.java:386)
        at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1052)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4098)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4030)
        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2490)
        at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2651)
        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2677)
        at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2134)
        at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2300)
        at com.sun.gjc.spi.jdbc40.PreparedStatementWrapper40.executeQuery(PreparedStatementWrapper40.java:642)
        at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeSelect(DatabaseAccessor.java:931)
        at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:607)
        ... 88 more
|#]

如您所见，它表示该表不存在，但存在我从我的本地主机数据库导出并导入到生产主机。 但仍然报错:

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'autolife.LOG' doesn't exist

我应该在这里做什么？

最佳答案

MySQL表名区分大小写depends on operating system ，我想这就是原因:

In MySQL, databases correspond to directories within the data directory. Each table within a database corresponds to at least one file within the database directory (and possibly more, depending on the storage engine). Consequently, the case sensitivity of the underlying operating system plays a part in the case sensitivity of database and table names. This means database and table names are not case sensitive in Windows, and case sensitive in most varieties of Unix. One notable exception is Mac OS X, which is Unix-based but uses a default file system type (HFS+) that is not case sensitive. However, Mac OS X also supports UFS volumes, which are case sensitive just as on any Unix.

因此，您需要明确地以正确的大小写设置表名:

@Entity @Table(name = "log")
public class Log implements Serializable { ... }

关于mysql - JPA:MySQL 说表不存在，但它实际上存在，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/10093718/