[DERBY-3621] Hibernate. Derby uses type 'text' as clob(255) instead of long varchar

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 10.3.2.1
• Fix Version/s: 10.4.1.3
• Component/s: Miscellaneous
• Environment: OS: Windows, Derby 10.3.2.1, Hibernate 3.1 (same problem with newer versions)
• Assignee: Unassigned
• Reporter: Aleksander Rozman
• Created: 15/Apr/08 17:38
• Updated: 21/Jan/11 18:16
• Resolved: 10/Jun/08 18:41

Description

Hi !

It seems that when type 'text' is used with Hibernate (indicating type text in database, which is varchar with no length defined-unlimited) Derby converts this definition to CLOB(255).

--------- Original code is set to

registerColumnType( Types.CLOB, "clob($l)" );

This then procudes CLOB(255), which means that Derby gives it only 255 character. Even if we dont use long varchar and use clob, we should at least give it max value for derby (this would fix most of problems, except in case where entry could be long varchar).

--------- This is my hack (which doesn't work)

I tried to "hack" hibernate and added following definition into DerbyDialect...
registerColumnType(Types.LONGVARBINARY, "long varchar for bit data");
registerColumnType(Types.LONGVARCHAR, "long varchar");
registerColumnType(Types.CLOB, "long varchar");

When I use type='text', then it always falls into Type.CLOB. This hack made it to be long varchar, which then produced error....

Caused by: java.sql.SQLDataException: An attempt was made to get a data value of type 'LONG VARCHAR' from a data value of type 'CLOB'.
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.newEmbedSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.newEmbedSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.generateCsSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.newSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.ConnectionChild.newSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedPreparedStatement.dataTypeConversion(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedPreparedStatement.setNull(Unknown Source)
at org.hibernate.type.NullableType.nullSafeSet(NullableType.java:76)
at org.hibernate.type.NullableType.nullSafeSet(NullableType.java:60)
at org.hibernate.persister.entity.AbstractEntityPersister.dehydrate(AbstractEntityPersister.java:1826)
at org.hibernate.persister.entity.AbstractEntityPersister.dehydrate(AbstractEntityPersister.java:1803)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2059)

------------------

Any kind of fix would be helpful. I am trying to find any pure java database that works with Hibernate... Each have their own problems... Hsqldb is to slow when used on USB (it works very fast, but shutdown is problem), Mckoi works very slow, but shgutdown is fast, this one doesn't work... Problem is that I need to have "portable" database, since my application should be also used on USB disk....

I hope this will be resolved...