Why has Hibernate switched to use LONG over CLOB?
clob, hibernate, java, oracle, orm
Solution
It looks like the resolution to this issue is to use `materialized_clob`, at least that's what's being said by Gail Badner on HHH-5569.
This doesn't help me at all (and I left relevant comment about that) but might be helpful for someone else here. Anyway the bug is rejected and there is very little I can do about it but use overriden dialect :(
Problem
It looks like that Hibernate started using `LONG` data type in version 3.5.5 (we upgraded from 3.2.7) instead of `CLOB` for the property of `type="text"`. This is causing problems as `LONG` data type in Oracle is an old outdated data type (see http://www.orafaq.com/wiki/LONG) that shouldn’t be used, and tables can’t have more than one column having `LONG` as a data type. Does anyone know why this has been changed? I have tried to set the Oracle `SetBigStringTryClob` property to true (as suggested in Hibernate > CLOB > Oracle :(), but that does not affect the data type mapping but only data transfer internals which are irrelevant to my case. One possible fix for this is to override the `org.hibernate.dialect.Oracle9iDialect`: ``` public class Oracle9iDialectFix extends Oracle9iDialect { public Oracle9iDialectFix() { super(); registerColumnType(Types.LONGVARCHAR, "clob"); registerColumnType(Types.LONGNVARCHAR, "clob"); } } ``` However this is the last resort - overriding this class is step closer to forking Hibernate which I would rather avoid doing. Can anybody explain why this was done? Should this be raised as a bug? [UPDATE]: I have created https://hibernate.atlassian.net/browse/HHH-5569, let's see what happens.