hibernate and middlegen and myisam

msousa · **Posted:** Tue Oct 05, 2004 6:05 pm

Hi,

I'm using hibernate 2.1, Middlegen 2.0-vo, MySQL 4.0.20d with MyISAM tables, mysql-connector-java-3.0.15-ga, ant 1.6.2, Linux 2.4.21-4.EL and everything seems to work fine. The gui comes up and I can view the tables of my database. Problem is the relationships are not visible. I ran ant with verbose flag and the following message was logged:

"WARNING: Middlegen couldn't find any relations between any tables."

I've noticed in the forum some posts regarding the driver for this problem, but this is the latest jdbc driver available from the MySQL site. Also, I will not be able to convert the tables from MyISAM to InnoDB. Is there anyway around this using Middlegen or possibly another tool similiar to Middlegen?

Thanks...

Mike

david · **Posted:** Tue Oct 05, 2004 9:53 pm

Here is some MySQL information from the Middlegen site:

Quote:

Requires MySQL 3.23.43b (or higher) with InnoDB enabled and MM.MySQL 2.0.9 or higher. The table names must be define in lower case, otherwise no relations will be discovered. If you have relations using foreign keys that consist of multiple columns, you should use the driver shipped with Middlegen. It has a bugfix which isn't yet fixed in the official driver.

On Win32 with MySQL 4.0.18 (or higher) + JDBC 3.0.14 (or higher), set lower_case_table_names=2 in my.ini. This will force InnoDB tables to be stored in lower-case, and will solve the above problem with relations discovery. The tables can still be referred to my their upper/proper case names, but will be converted to lower-case during the query. Not tested, but expect that lower_case_table_names to either 1 or 2 on Linux will have similar results.

Tested multi-column FKs with MySQL 4.0.20 and JDBC 3.0.14, and multi-column FKs appeared to work.

msousa · **Posted:** Wed Oct 06, 2004 2:10 pm

Thanks David,

I had seen those notes on the MySQL website. Unfortunately, I cannot change the tables in my database from MyISAM to InnuDB. My guess is I will just have to do the Hibernate mapping files by hand unless someone in this list knows of another way of automatically generating Hibernate mapping files for MySQL with MyISAM tables.

Thanks...

Mike

jaygarala · **Joined:** Tue Sep 14, 2004 10:57 am **Posts:** 12

Also becareful.. MyISAM are not transaction safe table type
http://dev.mysql.com/doc/mysql/en/Table_types.html

-Jay