环境：MySQL5+Hibernate3.2.5，使用JDK1.5
java代码大致这样的：
Session sess = MysqlFactory.openSession(); //MysqlFactory是我自己写得一个类
List list = new ArrayList();
try{
list = sess.createSQLQuery("select * from table_1").list();
sess.flush();
}catch(Exception ex){
ex.printStackTrace();
}finally{
MysqlFactory.closeSession();
}

错误Exception：
org.hibernate.MappingException: No Dialect mapping for JDBC type: -1
at org.hibernate.dialect.TypeNames.get(TypeNames.java:56)
at org.hibernate.dialect.TypeNames.get(TypeNames.java:81)
at org.hibernate.dialect.Dialect.getHibernateTypeName(Dialect.java:370)
at org.hibernate.loader.custom.CustomLoader$Metadata.getHibernateType(CustomLoader.java:559)
at org.hibernate.loader.custom.CustomLoader$ScalarResultColumnProcessor.performDiscovery(CustomLoader.java:485)
at org.hibernate.loader.custom.CustomLoader.autoDiscoverTypes(CustomLoader.java:501)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1796)
at org.hibernate.loader.Loader.doQuery(Loader.java:674)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:236)
at org.hibernate.loader.Loader.doList(Loader.java:2220)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2104)
at org.hibernate.loader.Loader.list(Loader.java:2099)
at org.hibernate.loader.custom.CustomLoader.list(CustomLoader.java:289)
at org.hibernate.impl.SessionImpl.listCustomQuery(SessionImpl.java:1695)
at org.hibernate.impl.AbstractSessionImpl.list(AbstractSessionImpl.java:142)
at org.hibernate.impl.SQLQueryImpl.list(SQLQueryImpl.java:152)
at org.apache.jsp.jsp.ad.do_.download_005fquestionnaire_jsp._jspService(download_005fquestionnaire_jsp.java:104)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at com.ibm.crl.inkfish.filters.UserManageFilter.doFilter(UserManageFilter.java:98)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at com.ibm.crl.inkfish.filters.EncodingFilter.doFilter(EncodingFilter.java:31)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:263)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:584)
at org.apache.tomcat.util.net.JIoEndpoint$Work