How do you map a boolean in Oracle

ppastor · **Joined:** Wed Jul 12, 2006 5:27 pm **Posts:** 4

All,

I have used nHibernate in the past with SQL Server with great success, and have now embarked on an Oracle project. My business objects, of course, have boolean properties. Since Oracle does not have a "bit" data type like SQL Server, what is the recommended method for handling this?

I have tried mapping to NUMBER(1,0), but get a cast exception. I have also tried a CHAR(1) with the same results. I am trying to avoid a lot of clunky code to work around this, so is there something already provided that I am just missing?

Any help is GREATLY appreciated.

Thank you,

dslevine · **Joined:** Thu May 26, 2005 12:20 am **Posts:** 72

You are totally on the right path. I use NUMBER(1) with Oracle, but I think NUMBER(1,0) should work.

Are you now using the OracleDialect?

Code:

hibernate.dialect=org.hibernate.dialect.OracleDialect

I think that is all you need to do to substitute TRUE => 1 and FALSE => 0. And then you map the fields as "boolean" in your hibernate config files and in your Java objects.

Is this what you are doing and it's not working?

ppastor · **Joined:** Wed Jul 12, 2006 5:27 pm **Posts:** 4

Dan,

Thanks for the reply.

Upon further review, it does work just fine with normal booleans. My issue is with the Nullables. As soon as I switch the mapping file over to the NullableBooleanType I get the cast exception IF there is a value in the database. If the value in the db is null, then it is fine.

Any thoughts?

Phil

dslevine · **Joined:** Thu May 26, 2005 12:20 am **Posts:** 72

I have not worked with those objects, but some things come to mind. Are you using java.lang.Boolean objects for your mapping types and Java fields? (as opposed to the primitive 'boolean' type)

ppastor · **Joined:** Wed Jul 12, 2006 5:27 pm **Posts:** 4

This is a .NET 2.0 application, and I am using the nullable boolean (bool?).

dslevine · **Joined:** Thu May 26, 2005 12:20 am **Posts:** 72

Sorry about that. I ended up in the NHibernate forum without realizing it when viewing unanswered posts.

Aleksei Kachanov · **Joined:** Tue Apr 25, 2006 8:08 am **Posts:** 2

How map 'Y'/'N' chars to NHibernate?
Unfortunetly I can't change database :(

Aleksei Kachanov · **Joined:** Tue Apr 25, 2006 8:08 am **Posts:** 2

How map 'Y'/'N' (varchar2(1)) chars to NHibernate?
Unfortunetly I can't change database :(

dslevine · **Joined:** Thu May 26, 2005 12:20 am **Posts:** 72

<prop key="hibernate.query.substitutions">true Y, false N</prop>

jemiller · **Posted:** Tue Jul 18, 2006 1:06 pm

As far as I know, all you should have to do is the following. I haven't tried boolean with Oracle specifically, but, I did something similar with with a nullable DateTime. Basically, I think you just tell the the .NET type (for nullables). I'm not sure if this is even necessary at this point. I got it to work this way, but, when I did that it was with a nightly build from awhile ago. Maybe it can detect better now. You shouldn't have to specify database specific types. The dialect should take care of that for you.

Code:

--Please rate me if this helps.

rponton · **Posted:** Tue Jul 18, 2006 5:17 pm

I just use type="YesNo".

Code:

ppastor · **Joined:** Wed Jul 12, 2006 5:27 pm **Posts:** 4

What is a YesNo type?