As you can learn from
How to batch INSERT and UPDATE statements with Hibernate (by
Vlad Mihalcea), by default, Hibernate doesn't have the batch feature active. In order to activate it, just configure the
hibernate.jdbc.batch_size property (e.g. between 5 and 30) as in the above article. For example, you can configure it depending on dialect bach size like this:
public static
int batchSize() {
return
Integer.valueOf(Dialect.DEFAULT_BATCH_SIZE);
}
properties.put("hibernate.jdbc.batch_size",
String.valueOf(batchSize()));
Now, let's see three examples of Spring 4 MVC approaches that uses Hibernate batch for some inserts:
- Using JpaRepository:
public interface ProductRepository extends JpaRepository<Product, Long> {
// NOPE
}
And ...
@Autowired
private ProductRepository productRepository;
...
@Override
@Transactional
public void withBatching(int n) {
// preparing the products
ArrayList<Product> productsInBatch = new ArrayList<>();
for (int i = 0; i < n; i++) {
Product p = new Product(i);
productsInBatch.add(p);
}
long start = System.nanoTime();
// persist via batching
productRepository.save(productsInBatch);
LOG.log(Level.INFO, "INSERTED {0} PRODUCTS IN: {1} MILISECONDS.",
new Object[]{n, TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start)});
}
The complete example is available
here.
- Using JpaContext:
@Autowired
private JpaContext jpaContext;
...
@Override
@Transactional
public void withBatching(int n) {
EntityManager em = jpaContext.getEntityManagerByManagedType(Product.class);
long start = System.nanoTime();
int batchSize = ...;
// persist via batching
for (int i = 0; i < n; i++) {
Product p = new Product(i);
em.persist(p);
// Flush a batch of inserts and release memory
if (i % batchSize == 0 && i > 0) {
em.flush();
em.clear();
}
}
LOG.log(Level.INFO, "INSERTED {0} PRODUCTS IN: {1} MILISECONDS.",
new Object[]{n, TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start)});
}
The complete example is available
here.
- Using PersistenceContext:
@PersistenceContext
private EntityManager entityManager;
And ...
@Autowired
private ProductDAO productDAO;
@Override
@Transactional
public void withBatching(int n) {
long start = System.nanoTime();
// persist via batching
productDAO.persistWithBatching(n);
LOG.log(Level.INFO, "INSERTED {0} PRODUCTS IN: {1} MILISECONDS.",
new Object[]{n, TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start)});
}
The complete example is available
here.
For a batch size of 15, in all examples you should get an output as below:
