Oracle错误汇总：

1.ERROR: HHH000319: Could not get database metadata
java.sql.SQLException: Listener refused the connection with the following error:
ORA-12505, TNS:listener does not currently know of SID given in connect descriptor

at oracle.jdbc.driver.SQLStateMapping.newSQLException(SQLStateMapping.java:70)
at oracle.jdbc.driver.DatabaseError.newSQLException(DatabaseError.java:131)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:197)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:525)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:413)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:508)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:203)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:33)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:510)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:154)
at org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl.getConnection(DriverManagerConnectionProviderImpl.java:173)
at org.hibernate.tool.hbm2ddl.SuppliedConnectionProviderConnectionHelper.prepare(SuppliedConnectionProviderConnectionHelper.java:51)
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:194)
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:178)
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:480)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1740)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1778)
at hibernate.conn.HibernateUitl.<clinit>(HibernateUitl.java:17)
at hibernate.conn.UserDAOImpl.findUserByName(UserDAOImpl.java:34)
at hibernate.conn.TestDAO.main(TestDAO.java:22)
Caused by: oracle.net.ns.NetException: Listener refused the connection with the following error:
ORA-12505, TNS:listener does not currently know of SID given in connect descriptor

at oracle.net.ns.NSProtocol.connect(NSProtocol.java:361)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:966)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:292)
... 16 more
2013-1-17 10:08:44 org.hibernate.tool.hbm2ddl.SchemaUpdate execute

解决方法：
SQL> alter database open;

数据库已更改。


3.ora-00923 未找到要求的from语句;
有说到oracle的方言设置出错，于是在hiberna的配置文件中将方言改为

<property name="hibernate.dialect">org.hibernate.dialect.Oracle9Dialect</property>

问题解决。

上网再了解一下方言：

因为不同的数据库，在Sql语句的设计上是存在差异的，就好比不同地方的人说不同的方言。而Hibernate呢，它会所有的“方言”，我们要做的，就是告诉它，我们需要它说哪种“方言”。

 <!--MySql 驱动程序 eg. mysql-connector-java-5.0.4-bin.jar-->
  <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
  <property name="connection.driver_class">com.mysql.jdbc.Driver</property>

  <!-- JDBC URL -->
  <property name="connection.url">jdbc:mysql://localhost/dbname?characterEncoding=gb2312</property>

  <!-- 数据库用户名-->
  <property name="connection.username">root</property>

  <!-- 数据库密码-->
  <property name="connection.password">root</property>
  
  
  <!--Sql Server 驱动程序 eg. jtds-1.2.jar-->
  <property name="dialect">org.hibernate.dialect.SQLServerDialect</property>
  <property name="connection.driver_class">net.sourceforge.jtds.jdbc.Driver</property>

  <!-- JDBC URL -->
  <property name="connection.url">jdbc:jtds:sqlserver://localhost:1433;DatabaseName=dbname</property>

  <!-- 数据库用户名-->
  <property name="connection.username">sa</property>

  <!-- 数据库密码-->
  <property name="connection.password"></property>

  
  
  <!--Oracle 驱动程序 ojdbc14.jar-->
  <property name="dialect">org.hibernate.dialect.OracleDialect</property>
  <property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>

  <!-- JDBC URL -->
  <property name="connection.url">jdbc:oracle:thin:@localhost:1521:dbname</property>

  <!-- 数据库用户名-->
  <property name="connection.username">test</property>

  <!-- 数据库密码-->
  <property name="connection.password">test</property>

则可能是Hibernate SQL方言 (hibernate.dialect)设置不正确。
Caused by: java.sql.SQLException: [Microsoft][SQLServer 2000 Driver for JDBC][SQLServer]'last_insert_id' 不是可以识别的 函数名。

RDBMS	方言
DB2	org.hibernate.dialect.DB2Dialect
DB2 AS/400	org.hibernate.dialect.DB2400Dialect
DB2 OS390	org.hibernate.dialect.DB2390Dialect
PostgreSQL	org.hibernate.dialect.PostgreSQLDialect
MySQL	org.hibernate.dialect.MySQLDialect
MySQL with InnoDB	org.hibernate.dialect.MySQLInnoDBDialect
MySQL with MyISAM	org.hibernate.dialect.MySQLMyISAMDialect
Oracle (any version)	org.hibernate.dialect.OracleDialect
Oracle 9i/10g	org.hibernate.dialect.Oracle9Dialect
Sybase	org.hibernate.dialect.SybaseDialect
Sybase Anywhere	org.hibernate.dialect.SybaseAnywhereDialect
Microsoft SQL Server	org.hibernate.dialect.SQLServerDialect
SAP DB	org.hibernate.dialect.SAPDBDialect
Informix	org.hibernate.dialect.InformixDialect
HypersonicSQL	org.hibernate.dialect.HSQLDialect
Ingres	org.hibernate.dialect.IngresDialect
Progress	org.hibernate.dialect.ProgressDialect
Mckoi SQL	org.hibernate.dialect.MckoiDialect
Interbase	org.hibernate.dialect.InterbaseDialect
Pointbase	org.hibernate.dialect.PointbaseDialect
FrontBase	org.hibernate.dialect.FrontbaseDialect
Firebird	org.hibernate.dialect.FirebirdDialect