I have a problem with mapping many-to-one relationship without exact foreign key constraint set in database. I use OpenJPA implementation with MySql database, b开发者_如何学Pythonut the problem is wit
I am working on a JPA project. I need to use a @OneToMany mapping on a class that has three primary keys. You can find the errors and the classes after this.
I have been working on it for quite a while, but still can\'t figure out what\'s wrong with my code. Each Service has multiple profiles, but each profile only has one Service.
After having changed around my mappings a bit ( see my other question about cascade-delete for reasons) , i tried inserting a completely new object and all its subclasses.
I\'m piggy-backing off of How to join tables in unidirectional many-to-one condition?. If you have two classes:
I hope someone can help me find an answer. I\'m working with a legacy database and I can\'t change any of the preexisting tables, because other apps depend on them.
I have Country and State objects. I intend to have unidirectional many to one relationship from State to Country. I don\'t want to store any references to States in Country I have defined mapping as b
I have a project of converting one database to another. One of the original database columns defines the row\'s category. This column should be mapped to a new category in the new database.
Hey all,I\'m kicking the tires on NHibernate and have a conoundrum I have been scratching my head over for a bit now, working with a legacy database with some fairly complex relationships.
I\'ve been battling this for a while. I\'m trying to implement a many to one association. I have a bunch of rows in a table, called readings. These accumulate over time, and every now and then I want
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