Saving database records problem

[Milutin Markovic]

I have 3 tables (MySQL). Invoice, product and JoinTable InvoiceItems.
When I have new Invoice, I select one ore more products from Product table.
I need insert one row in Invoice table and one or more rows in InvoiceItems table. Product table not change.
I geting error that column 'idinvoice' cannot be null. Can somebody help me please please please.
You may see picture of tables relationship below (attachment).

  @Entity
  @Table(name = "invoice")
public class Invoice implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id")
    private Integer id;
    *
    *
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "invoice")
    private Collection<InvoiceItems> invoiceItemsCollection;
    *
    *

  @Entity
  @Table(name = "invoiceItems")
  public class InvoiceItems implements Serializable {
    private static final long serialVersionUID = 1L;
    @EmbeddedId
    protected InvoiceItemsUPK invoiceItemsUPK;
    *
    *
    @JoinColumn(name = "idproduct", referencedColumnName = "id", insertable = false, updatable = false)      
    @ManyToOne(optional = false)
    private Product product;
    @JoinColumn(name = "idinvoice", referencedColumnName = "id", insertable = false, updatable = false)
    @ManyToOne(optional = false)
    private Invoice invoice;
    *
    *

    @Entity
    @Table(name = "product")
    public class Product implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id")
    private Integer id;
    *
    *
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "product")
    private Collection<InvoiceItems> invoiceItemsCollection;

Backing bean part

    invoiceItem.setProduct(product);
    invoiceItem.set...
    *
    *
    invoiceItem.set...
    Collection<InvoiceItems> invoiceItem1Collection= product.getInvoiceItemsCollection();
    invoiceItem1Collection.add(invoiceItem);
    product.setInvoiceItems(invoiceItem1Collection);
    Collection<InvoiceItems> invoiceItem2Collection= invoice.getInvoiceItemsCollection();
    invoiceItem2Collection.add(invoiceItem);
    invoice.setInvoiceItems(invoiceItem2Collection);
    EntityManager em.persist(invoice);
    *
    *

Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.0.1.v20100213-r6600): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Column 'idinvoice' cannot be null
Error Code: 1048
Call: INSERT INTO fakstavke_u (CenaStr, trosakproc, mpc, Nabavna, pdv, Kolicina, vpc, marza, Rabat, trosak, marzaproc, Cena, idproduct, idinvoice) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
bind => [1.0, 0.0, 450.0, 450.0, 18, 1.0, 450.0, 0.0, 0.0, 0.0, 0.0, 450.0, null, null]
Query: InsertObjectQuery(entity.InvoiceItems[invoiceItemsUPK=null])
at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:324)
*
*

[Ram Narayan.M]

The column "idinvoice" has been declared with the constraint "Not Null" in DB.

And you have given the annotation

[b]@JoinColumn(name = "idinvoice", referencedColumnName = "id", insertable = false, updatable = false)[/b]

"insertable=false" which stops to insert the value into the "idinvoice" column... So, the INSERT Query is constructed with "NULL" value to be inserted into that column...

Due to the "Not Null" constraint, you are getting such error... make it as "insertable=true" or remove that[ by default insertable is true]

[Milutin Markovic]

I have error in my queston. Idproduct cannot be null but I understood you and fix that. Thanks thanks thanks.

But when idproduct column is insertable=true I get error that column specified twice. Same with column idinvoice.

Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.0.1.v20100213-r6600): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Column 'idproduct' specified twice
Error Code: 1110
Call: INSERT INTO invoiceItems (CenaStr, trosakproc, mpc, Nabavna, pdv, Kolicina, vpc, marza, Rabat, trosak, marzaproc, Cena, idproduct, idproduct, idinvoice, idinvoice) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
bind => [1.0, 0.0, 470.0, 470.0, 18, 1.0, 470.0, 0.0, 0.0, 0.0, 0.0, 470.0, null, null, null, null]
Query: InsertObjectQuery(entity.invoiceItems[invoiceItemsUPK=null])

Why have duplicate column? I will try to solve that tomorow. I am glad that I rid of error 1048 that troubling me two days.