Cannot insert null into a non nullable column (Object Relational Mapping forum at Coderanch)

Post by: anagha desai , Greenhorn

May 08, 2008 23:55:00

Hello ,
Am new to JPA / Hibernate / ORM

Facing a strange issue .

1 >Created a simple table in HSQLDB
2 >Then using JPA tried persisting the data - and it worked fine

Here in DB had not defined the primary key explicitly

Now I tried to use the "Embedded" attribute
( Single Table - but two Java objects )

The problem that I am facing is that if I use :

it works fine

For other options ( AUTO , IDENTITY ) get the exception ::
Caused by: java.sql.SQLException: Attempt to insert null into a non-nullable column: column: CUST_ID

Can anyone provide some pointers related to ::
1 >
when I dont use @embedded & @Embeddable I can simply do an insert using GenerationType.AUTO - This works

2 >
when I use @embedded & @Embeddable I CANNOT do an insert unless I use
GenerationType.SEQUENCE

Thanks ,
anagha

Post by: Mark Spritzler , Sheriff

May 09, 2008 09:13:00

Sorry, I might just be confused, but embedded objects won't have an @Id on it, since it is a dependant object on another object, and that object will have the pk.

Embedded is a case where, for example, you have this table, and you want two seperate objects in Java to represent all the stuff in that one table.

Example

Table User
Fields:

id
firstname
lastname
street
city
state
zip

And you want a User and an Address object to represent all the fields in that User table.

Address object doesn't have the id, it is in the User object. So Address is an Embedded object for the User object.

Hope that helps clear some things up if I am correctly understanding what you are asking.

Mark