Question

I am using hibernate framework to be able to use Oracle or Sybase (customer choice). But when we switch the connection to Sybase, I have some issues about many-to-one constraint. First of all, Oracle complained for clob fields which have been defined as “text” in hibernate_hbm.xml and I solved this issue with using binary (ClobTypeDescriptor.STREAM_BINDING) in custom type. For Oracle, everything is normal and works perfect. But when I switch the db server to Sybase, I get the following error when trying to save record(s) on table which have foreign key constraint.

Caused by: java.sql.SQLException: JZ006: Caught IOException: java.io.IOException: JZ0SL: Unsupported SQL type 2005.
        at com.sybase.jdbc4.jdbc.SybConnection.getAllExceptions(Unknown Source)
        at com.sybase.jdbc4.jdbc.SybStatement.handleSQLE(Unknown Source)
        at com.sybase.jdbc4.jdbc.SybStatement.sendQuery(Unknown Source)
        at com.sybase.jdbc4.jdbc.SybPreparedStatement.sendQuery(Unknown Source)
        at com.sybase.jdbc4.jdbc.SybStatement.executeUpdate(Unknown Source)
        at com.sybase.jdbc4.jdbc.SybPreparedStatement.executeUpdate(Unknown Source)
        at org.hibernate.id.IdentityGenerator$GetGeneratedKeysDelegate.executeAndExtract(IdentityGenerator.java:94)
        at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:57)
        ... 47 more

Here is the mapping:

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.aykut.test.persistence">

    <class name="classA" table="tableA">
        <id name="tableA_Id" type="long">
            <generator class="native" />
        </id>
        <property name="someDateColumn" type="timestamp" />
        <set name="destinations" table="tableB" cascade="all" lazy="false">
            <key column="tableA_Id" />
            <one-to-many class="classB" />
        </set>
    </class>
    <class name="classB" table="tableB">
        <id name="tableB_Id" type="long">
            <generator class="native" />
        </id>
        <many-to-one name="classA_Data" class="classA" column="tableA_Id" lazy="false" />
        <property name="someInfoColumn" length="64" not-null="true" type="string" />
    </class>
</hibernate-mapping>

I run some tests and if there is no any relation between these two tables, records can be saved normally.

There is some weirdness to me like, if I create tables with ddl manually and give bigint type to id columns and if I don’t use hibernate.hbm2ddl.auto=update property, everything looks normal. Columns created in bigint type and works fine.

if I use hibernate.hbm2ddl.auto=update property, tables created with numeric(19,0) fields for id columns. When this happen, our mapping is thrown above error.

I read some article and I test them but there is no success. Here is my tests.

---

Adding mapping to not-null=”true” <many-to-one name="classA_Data" class="classA" column="tableA_Id" /> row. FAILED

Adding hibernate.max_fetch_depth = 1 to properties. FAILED.

Adding hibernate.jdbc.use_get_generated_keys=true to properties. FAILED.

These all are happens for Sybase side.

I tested both jconnect 6.0(jdbc3) and 7.0 (jdbc4)

I am using hibernate 3.6.1 final.
Tested with Oracle11gR2 and Sybase 12.0.5 – 15.0.2 – 15.0.3

Any suggestion please?

Answer 1

I have figured out what was the actual problem and solved it. We use custom type for clob field for oracle instances.(This was another solution for oracle.) but when we implemented this custom type, sybase instances started to throw above exception. At the beginning, I thought the problem is constraints but not at all. Problem was; trying to set null to clob fields for sybase clob type.I implemented the overrided nullSafeSet method on our custom type class as if value is null for custom type, convert type to varchar. Also we have had to create new texttypedescriptor for sybase clob fields. Then it works. Here is the solution:

import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Types;

import org.hibernate.HibernateException;
import org.hibernate.engine.SessionImplementor;
import org.hibernate.type.AbstractStandardBasicType;
import org.hibernate.type.descriptor.java.StringTypeDescriptor;
import org.hibernate.type.descriptor.sql.ClobTypeDescriptor;

public class TextType extends AbstractStandardBasicType<String> {

    public static final TextType INSTANCE = new TextType();

    public TextType() {
        super((myapp.isOracle?ClobTypeDescriptor.STREAM_BINDING:CustomSybaseTextTypeDescriptor.INSTANCE), StringTypeDescriptor.INSTANCE);
    }

    public String getName() {
        return "customtext";
    }

    @Override
    public void nullSafeSet(PreparedStatement arg0, Object arg1, int arg2,
            boolean[] arg3, SessionImplementor arg4)
            throws HibernateException, SQLException {
        if(arg1 == null)
            arg0.setNull(arg2,Types.VARCHAR);
        else
            super.nullSafeSet(arg0, arg1, arg2, arg4);
    }
}