Hi, In general this type of relationship should be just fine. Could you please check if your DB relationships have the 'to Dep Pk' flag set properly. In your case it should be set on meals and meals_items parts and not set on the meals_meals_items part of the relationship.
It's a pretty common source of the troubles, as it's not the most obvious checkbox. But it is required in order for Cayenne to decide what part of the PK to PK relationship is leading. On Wed, Apr 12, 2023 at 9:34 AM Markus Reich <reich.mar...@gmail.com> wrote: > > Hi, > > I'm using Cayenne 4.2.RC2 and have a special problem when deleting or > creating objects that have a relation to others. > To solve the problem I have to delete the FK relation on database. I'm > using MariaDB 10.9. with the JDBC driver org.mariadb.jdbc 3.1.3. > > My model > > meals > meals_meals_items > meals_items > > meals 1 : n meals_items > the relation is in meals_meals_items > so meals_meals_items has two fk one to meal_id and one to meal_item_id > > I try to create a meal with two meals_items > the log looks like > > 2023-04-12 08:29:01,423 INFO [org.apache.cayenne.log.JdbcEventLogger]: > INSERT INTO `balecon`.`meals_meals_items`( `meal_id`, `meal_item_id`) > VALUES( ?, ?) > > 2023-04-12 08:29:01,423 INFO [org.apache.cayenne.log.JdbcEventLogger]: > [batch bind: 1->meal_id:'d845fda8-ad39-47f9-98dd-5062ce...', > 2->meal_item_id:'d2b8082f-9318-4a71-b27d-c51ae7...'] > > 2023-04-12 08:29:01,423 INFO [org.apache.cayenne.log.JdbcEventLogger]: > [batch bind: 1->meal_id:'d845fda8-ad39-47f9-98dd-5062ce...', > 2->meal_item_id:'67f4bbfe-8837-43c3-b722-aedd29...'] > > 2023-04-12 08:29:01,435 INFO [org.apache.cayenne.log.JdbcEventLogger]: *** > error. > > java.sql.BatchUpdateException: (conn=19509) Cannot add or update a child > row: a foreign key constraint fails (`balecon`.`meals_meals_items`, > CONSTRAINT `fk_meals_items` FOREIGN KEY (`meal_item_id`) REFERENCES > `meals_items` (`id`)) > > > so cayenne tries to insert the meals_meals_items before the inserts of > meals_items? > > > sometimes it works, but then the deleting has problem, also first he trys > to delete meals_meals_items then the fk has a problem? > > > regards > > Meex > > > > > > When I log the JDBC statements I see -- Best regards, Nikita Timofeev
