Noob error :org.hibernate.exception.SQLGrammarException: could not insert [com.sample.Person]

[Vic Hood]

I'm trying to set up a small working sample of Hibernate that I found here.
However when I run the code I get the follwing error
.

  Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not insert: [com.sample.Person]
	at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:92)
	at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
	at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:64)
	at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2345)
	at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2852)
	at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:71)
	at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:273)
	at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:320)
	at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:203)
	at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:129)
	at .....


    Caused by: org.postgresql.util.PSQLException: ERROR: relation "person" does not exist
    Position: 13
	at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2102)
	at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1835)
	at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257)
	at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:500)
	at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:388)
	at org.postgresql.jdbc2.AbstractJdbc2Statement.executeUpdate(AbstractJdbc2Statement.java:334)
	at org.hibernate.id.IdentityGenerator$GetGeneratedKeysDelegate.executeAndExtract(IdentityGenerator.java:94)
	at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:57)
	... 23 more

But I already have a table by the name person in the database and here's my hibernate.cfg.xml

<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <!-- hibernate dialect --> <property name="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</property> <property name="hibernate.connection.driver_class">org.postgresql.Driver</property> <property name="hibernate.connection.url">jdbc:postgresql://localhost/testDB</property> <property name="hibernate.connection.username">postgres</property> <property name="hibernate.connection.password"></property> <property name="hibernate.show.sql" ></property> <property name="transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property> <!-- Automatic schema creation (begin) === --> <property name="hibernate.hbm2ddl.auto">create</property> <!-- Simple memory-only cache --> <property name="hibernate.cache.provider_class">org.hibernate.cache.HashtableCacheProvider</property> <!-- Enable Hibernate's automatic session context management --> <property name="current_session_context_class">thread</property> <!-- ############################################ --> <!-- # mapping files with external dependencies # --> <!-- ############################################ --> <mapping resource="com/sample/Person.hbm.xml" /> </session-factory> </hibernate-configuration> Person.hbm.xml [code=xml] <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping> <class name="com.sample.Person" table="person"> <id name="id" column="ID"> <generator class="native" /> </id> <property name="name"> <column name="NAME" length="16" not-null="true" /> </property> <property name="surname"> <column name="SURNAME" length="16" not-null="true" /> </property> <property name="address"> <column name="ADDRESS" length="16" not-null="true" /> </property> </class> </hibernate-mapping>

Content of the postgresql log file
2012-02-13 09:23:25 IST LOG: database system was shut down at 2012-02-10 18:14:57 IST 2012-02-13 09:23:25 IST FATAL: the database system is starting up 2012-02-13 09:23:33 IST LOG: database system is ready to accept connections 2012-02-13 09:23:38 IST LOG: autovacuum launcher started 2012-02-13 09:46:01 IST ERROR: syntax error at or near "auto_increment" at character 41 2012-02-13 09:46:01 IST STATEMENT: create table person (ID bigint not null auto_increment, NAME varchar(16) not null, SURNAME varchar(16) not null, ADDRESS varchar(16) not null, primary key (ID)) type=InnoDB 2012-02-13 09:46:01 IST ERROR: relation "person" does not exist at character 13 2012-02-13 09:46:01 IST STATEMENT: insert into person (NAME, SURNAME, ADDRESS) values ($1, $2, $3) RETURNING * 2012-02-13 09:46:01 IST LOG: could not receive data from client: No connection could be made because the target machine actively refused it. 2012-02-13 09:46:01 IST LOG: unexpected EOF on client connection 2012-02-13 09:48:15 IST ERROR: syntax error at or near "auto_increment" at character 41 2012-02-13 09:48:15 IST STATEMENT: create table person (ID bigint not null auto_increment, NAME varchar(16) not null, SURNAME varchar(16) not null, ADDRESS varchar(16) not null, primary key (ID)) type=InnoDB 2012-02-13 09:48:15 IST ERROR: relation "person" does not exist at character 13 2012-02-13 09:48:15 IST STATEMENT: insert into person (NAME, SURNAME, ADDRESS) values ($1, $2, $3) RETURNING * 2012-02-13 09:48:15 IST LOG: could not receive data from client: No connection could be made because the target machine actively refused it. 2012-02-13 09:48:15 IST LOG: unexpected EOF on client connection

It would be great if anyone could point out what Im doing wrong, as this is my first attempt at Hibernate.
Thanks!

[Vic Hood]

UPDATE: Was able to fix that error. However I get the following error now

Hibernate: insert into person (NAME, SURNAME, ADDRESS) values (?, ?, ?)
Hibernate: select person0_.ID as ID0_, person0_.NAME as NAME0_, person0_.SURNAME as SURNAME0_, person0_.ADDRESS as ADDRESS0_ from person person0_
Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not execute query
	at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:92)
	at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
	at org.hibernate.loader.Loader.doList(Loader.java:2536)
	at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2276)
	at org.hibernate.loader.Loader.list(Loader.java:2271)
	at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:452)
	at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:363)
	at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
	at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1268)
	at org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
	at com.sample.TestPerson.queryPerson(TestPerson.java:24)
	at com.sample.TestPerson.main(TestPerson.java:18)
Caused by: org.postgresql.util.PSQLException: ERROR: column person0_.id does not exist
  Position: 8
	at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2102)
	at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1835)
	at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257)

What I dont understand is why is hibernate looking at person0_ instead of person, any input on this could be helpful. Thanks!

[Nanda P Kumar]

It is because hibernate queries are later converted to sql queries and table aliases are created in the queries. In this case, person0_ is an alias for the table person.