I have a primary key column which is an INT column which I would like to change to a BIGINT. Our test and production environment uses MySQL, but for unit tests we use the embedded H2 database.

I have created the following Liquibase refactoring:

```xml
...
<changeSet id="1" author="trond">
    <modifyDataType tableName="event" columnName="id" newDataType="BIGINT" />
    <rollback>
        <modifyDataType tableName="event" columnName="id" newDataType="INT" />
    </rollback>
</changeSet>
...

```

The refactoring works, but when I try to persist an object to the database using Hibernate, I get the following error message (I've wrapped the error message):

```
ERROR org.hibernate.util.JDBCExceptionReporter [main]: NULL not allowed for column "ID"; 
    SQL statement: insert into event (id, eventtime, guid, meta, objectguid, originatorid, subtype, type) values (null, ?, ?, ?, ?, ?, ?, '0') [90006-140]

JDBC exception on Hibernate data access: 
    SQLException for SQL [insert into event (id, eventtime, guid, meta, objectguid, originatorid, subtype, type) values (null, ?, ?, ?, ?, ?, ?, '0')]; 
    SQL state [90006]; error code [90006]; could not insert: [event.MyEvent]; 
    nested exception is org.hibernate.exception.GenericJDBCException: could not insert: [event.MyEvent]

```

The MyEvent class inherits from a AbstractBaseEvent which has defined the following Hibernate mapping in the code:

```java
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private long id;

```

A few points:

* The hibernate mapping works before the refactoring of the data type
* Version of Liquibase is 2.0.1
* Whether or not this works with MySQL hasn't been tested yet