Data does not save while calling persist() multiple times

Question

I am trying to persist to multiple entities. Sample code below:

public List<String> save(SalesInvoice salesInvoice, List<ClosingStock> closingStockList, Company company,
        Receipt receipt) {

    log.info("Saving Sales Invoice...");
    if (salesInvoice.getSalesChallanId() == null) {
        for (ClosingStock closingStock : closingStockList) {
            if (existingClosingStock(closingStock.getProduct().getId().toString()) == null) {
                em.persist(closingStock);
            } else {

            }
        }
    }
    em.persist(salesInvoice);
    receipt.setSalesInvoiceId(salesInvoice.getId());
    em.persist(receipt);
    return null;
}

// Edit: Add existingClosingStock method provided in comments

public ClosingStock existingClosingStock(String productId) { 
    try { 
        return (ClosingStock) em.createQuery("SELECT cv FROM ClosingStock cv WHERE cv.product.id=:productId") .setParameter("productId", productId).getSingleResult(); 
    } catch (NoResultException e) { 
        return null; 
    } 
} 

Well, when I execute this query, the data didn't persist in database, but it shows the list of newly inserted data for small times, but data didn't save in database. I got no errors in console. Also put em.getTransaction().commit(); before return does not work. When I tried persisting on single entity and put em.getTransaction().commit(); , it worked perfectly. Like this:

public void save(Location location) {
    log.info("Saving Location.");
    em.persist(location);
    em.getTransaction().commit();
}

What did I miss here?

Answer 1

As explained in this article , persist just schedules an entity state transition . The insert is executed during flush. If you don't commit the transaction, the flush will not be triggered automatically.

Anyway, you should always start a transaction, even if you plan to read data.