Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>Hibernate does/can use bytecode generation (CGLIB) so that it knows a field is dirty as soon as you call the setter (or even assign to the field afaict).</p> <p>This immediately marks that field/object as dirty, but doesn't reduce the number of objects that need to be dirty-checked during flush. All it does is impact the implementation of <code>org.hibernate.engine.EntityEntry.requiresDirtyCheck()</code>. It <em>still</em> does a field-by-field comparison to check for dirtiness.</p> <p>I say the above based on a recent trawl through the source code (3.2.6GA), with whatever credibility that adds. Points of interest are:</p> <ul> <li><code>SessionImpl.flush()</code> triggers an <code>onFlush()</code> event.</li> <li><code>SessionImpl.list()</code> calls <code>autoFlushIfRequired()</code> which triggers an <code>onAutoFlush()</code> event. (on the tables-of-interest). That is, queries can invoke a flush. Interestingly, no flush occurs if there is no transaction.</li> <li>Both those events eventually end up in <code>AbstractFlushingEventListener.flushEverythingToExecutions()</code>, which ends up (amongst other interesting locations) at <code>flushEntities()</code>.</li> <li>That loops over every entity in the session (<code>source.getPersistenceContext().getEntityEntries()</code>) calling <code>DefaultFlushEntityEventListener.onFlushEntity()</code>.</li> <li>You eventually end up at <code>dirtyCheck()</code>. That method does make some optimizations wrt to CGLIB dirty flags, but we've still ended up looping over every entity.</li> </ul>
    singulars
    1. This table or related slice is empty.
    1. POWhen Hibernate flushes a Session, how does it decide which objects in the session are dirty?
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USBhesh Gurung
    1. USMatt Quail
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POWhen Hibernate flushes a Session, how does it decide which objects in the session are dirty?
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTAcceptedByOriginator
    1. COPlease, explain better: if the dirty flag doesn't reduce the number of objects that need to be dirty-checked what is its usefulness? Furtermore in the source I see two different dirty flags: one is in AbstractFieldInterceptor and is checked by EntityEntry.requiresDirtyCheck(), another one is in AbstractPersistentCollection and is commented "collections detect changes made via their public interface and mark themselves as dirty as a performance optimization" (I don't know where it's checked in the code).
      singulars
      1. PO
      1. USPino
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload