I have a car table and driver table. Each car can be driven by some drivers but one of them must be active driver and each dri开发者_StackOverflowver can drive one and only one car. I need to query fo
I\'ve got two tables (articles and tags) that have a one-to-many relationship. I remember seeing somewhere that I can create nested objects/arrays/etc from that relationship. The output of which I wo
I have the following classes: public class Parent { public virtual int ParentId { get; set; } public virtual string Name { get; set; }
When performing a delete of a one-many relationship without exposing the foreign key, EF deletes the parent record and tries to null the foreign key on the child records. This of course causes an erro
So, my question is: how to make possible that calls: Clan.win #to get all won rounds Clan.blue #to get all rounds when clan was in blue team
I\'m trying to remove a parent, but I keep getting a Foreign Key violation. If I put Cascade.ALL in the parent, it delete the children too.And it\'s now what I want.
Hibernate can do bidirectional polymorphism with TABLE_PER_CLASS (<union-subclass>), says so here:
Two class: DepartmentTask One department can have many tasks. One task can only belong to one department.
I have a to-many relationship between Entity A and Entity B (iOS Core Data app).I need to get the sum of the NSDecimalNumber attribute of all instances of Entity B from a given instance of Entity A.Do
I have two tables Person @Id @Column(name = \"PERSON_ID\") @GeneratedValue public Integer getId() { return id;
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