Hi,

I am new to hibernate. Could somebody please help me?
Thank you very much.

String hql= "select max(userID) from User";
List list = session.createQuery(hql).list();
int maxID = ( (Integer)list.get(0) ).intValue();

Error message:
Exception in thread "main" java.lang.IllegalStateException: No data type for node: org.hibernate.hql.ast.tree.IdentNode
+-[IDENT] IdentNode: 'userID' {originalText=userID}

at org.hibernate.hql.ast.tree.SelectClause.initializeExplicitSelectClause(SelectClause.java:140)
at org.hibernate.hql.ast.HqlSqlWalker.useSelectClause(HqlSqlWalker.java:702)
at org.hibernate.hql.ast.HqlSqlWalker.processQuery(HqlSqlWalker.java:531)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:645)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:281)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:229)
at org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:218)
at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:158)
at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:109)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:75)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:54)
at org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:71)
at org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:133)
at org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:112)
at org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1583)
at com.peng.hibernate.testMain.test(testMain.java:57)
at com.peng.hibernate.testMain.main(testMain.java:17)




<hibernate-mapping>
<class name="com.peng.hibernate.User" table="user" catalog="bookstore">
<id name="userId" type="java.lang.Integer">
<column name="userID" />
<generator class="assigned" />
</id>
<property name="name" type="java.lang.String">
<column name="name" length="45" not-null="true" />
</property>
<property name="password" type="java.lang.String">
<column name="password" length="20" not-null="true" />
</property> <set name="userroles" inverse="true">
<key>
<column name="userID" not-null="true" />
</key>
<one-to-many class="com.peng.hibernate.Userrole" />
</set>
</class>
</hibernate-mapping>

You should be using userId instead of userID in your max() function.
According to the hibernate mapping, userID is the column name..but your field name is "userId" which is what you'd have to use when you're using HQL. I believe its just a simple overlook due to the subtle difference...
Hope that fixes your problem!

- Arun

That's my mistake.
Thanks for helping! arun123

Thanks for posting that. You just saved me a HUGE headache. Even three years after you posted it.

Cheers

Steven