org.hibernate.exception.SQLGrammarException：无法执行语句

Question

I tried easy program at Hibernate and caught bunch of exception.

I couldn't figure out what exactly is wrong.

I have three classes - Book, Reader and Using. The last is binding first two with dependency one to many.

Here is my main() :

public class Appl {
    public static void main(String[] args) {
        Book book = new Book();
        book.setTitle("book01155");
        //
        Reader reader = new Reader();
        reader.setName("reader2");
        //
        Using using = new Using();
        using.setIdBook(book);
        using.setIdReader(reader);
        //
        List<Book> elements = new ArrayList<Book>();
        //
        Session session = null;     
        try {
            session = HibernateUtil.getSessionFactory().openSession();
            session.beginTransaction();
            session.save(book);
            session.save(reader);
            session.save(using);
            elements = session.createCriteria(Book.class).list();
            session.getTransaction().commit();
        } finally {
            if (session != null && session.isOpen()) {
                session.close();
            }
        }
        for (Book b : elements) {
            System.out.println("book: id=" + b.getIdBook() + " Title="
                    + b.getTitle());
        }
        System.out.println("\nThe END.\n");
    }
}

Here is exception message:

ERROR: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'USING (IDBOOK, IDREADER) values (2, 2)' at line 1
Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not execute statement
    at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:82)
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:125)

snippet of hiberante.cfg.xml :

<hibernate-configuration>
    <session-factory>
        <property name="eclipse.connection.profile">097Hibernate</property>

        <property name="connection.url">jdbc:mysql://localhost/_097_Library</property>
        <property name="connection.username">root</property>
        <property name="connection.password">secret</property>

        <!-- property name="hbm2ddl.auto">create</property -->
        <property name="hbm2ddl.auto">update</property>

        <property name="connection.driver_class">
            com.mysql.jdbc.Driver
        </property>

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

        <mapping class="com.softserve.edu.Book" />
        <mapping class="com.softserve.edu.Reader" />
        <mapping class="com.softserve.edu.Using" />
    </session-factory>
</hibernate-configuration>

All tables at DB are created but is empty. All looks ok. Any suggestions?

• How to solve this trouble?

Answer 1

In MySQL USING is reserved word .

So just rename the table by using @javax.persistence.Table annotation on your Using entity. Something like

@Entity
@Table(name = "TB_USING")
public class Using {
    ...
}

I assumed you have a table for USING , but you mentioned that it is a one-to-many relationship, so you can omit the table, and model it using just a single foreign key in Reader table.

By the way hibernate does not force you to create a new entity for many-to-many join tables (which don't have any more attribute but the foreign keys). But I believe it is a good practice to have an entity for that relationship, cause most of the times some attributes will be defined for the relation in future.

Answer 2

As Amir pointed out, there are reserved words, not just in MySQL but in Hibernate too.

See:

Reserved Words, Hibernate / JPA

Answer 3

The problem can be a result of conflicting MySQL versions for MySQL 5.x use org.hibernate.dialect.MySQL5Dialect then for anyother version use org.hibernate.dialect.MySQLDialect

Revised your hibernate.cfg.xml or .properties file

org.hibernate.dialect.MySQL5Dialect

Answer 4

In my case, colum name in oracle and in class was different. After i made them same, it solved.