About Cache


Wrong select results

Hello, I got a realy strange SELECT problem. In explorer query "select p  from Player p where p.confirmed==false", given me some results with p.confirmed==TRUE. And when I try to do (see image) "select p, p.confirmed  from Player p where p.confirmed==false", I getting p->confirmed->true and p.confirmed->false. How so? <odb v2.6.5_05> And this problem not only in explorer ... version-check="true" />   <processing cache="1024mb" max-threads="8" />   <query-cache results="1024mb" programs="500" />   <extensions ...


Performance Questions...

Greetings ObjectDB team, All below questions assume a very large database (~1,000,000,000 objects) Q1: Two queries with a big overlap between their result sets. If I query the first and hold them in memory somehow, would that speed up the execution of the second query since many of its result objects already created and reside in memory ? Q2: Do I need to manually use strong references to such cached result objects ? or do ObjectDB exploits frequency of querying such objects and keep them in memory longer automatically somehow before GC takes place ?... of the EntityManager's persistence context (L1) cache. But otherwise read only databases are not faster. Future versions of ObjectDB might share an L1 cache of read only entity managers automatically. Even though ObjectDB ...



The JDO Transaction interface provides for initiation and completion of transactions under user control.(Interface of JDO)



Annotation for defining the persistence of a member.(Annotation of JDO)


Replication issue, Replayer failing due to NullPointerException.

I'm getting replication errors and upon trying to play the replayer I get a NullPointerException which i'm also seeing in the slave logs when it's trying to replicate... ... = "true" /> <processing cache = "64mb" max-threads = "10" synchronized = "false" /> <query-cache results = "32mb" programs = "500" /> ... = "true" reflection = "error" /> <cache ref = "weak" level2 = "0mb" /> <persist ...


Advanced JPA Topics

Describes advanced JPA topics - detached entity objects, lock management and entity lifecycle events.... JPA Lifecycle Events Shared (L2) Entity Cache JPA Metamodel API ...


First query takes 4+ minutes to complete

Hi, we are evaluating ObjectDB 2.5.1_04 in embedded mode hoping to replace SQLite in our application. We observed that in our case it takes on average more than 4 minutes to complete the first SELECT query that we run on the DB which contains about 320,000 records of a single type of object. SQLite in comparison responds within few seconds on average with the same number of records. We hope to receive your recommendation on how to improve this result with this post.   Test System ... = "true" /> <processing cache = "256mb" max-threads = "10" /> <query-cache results = "64mb" programs = "50" /> ... "false" reflection = "warning" /> <cache ref = "weak" level2 = "512mb" /> <persist ...


PersistenceException: Failed to locate field

Hi, have recently been running into this issue when changing the schema: com.objectdb.o._PersistenceException: Failed to locate field in this case, adding a primitive String field to an Entity. pretty sure that in the past schema evolution would not have triggered errors, is this case, a simple new field, shouldn't the policy be to add a null in that field, or other default for that primitive. ... reflection = "warning" />   <cache ref = "weak" level2 = "20m" />   <fetch ... = "true" reflection = "warning" /> <cache ref = "weak" level2 = "20m" /> <fetch hollow = ...



... Fixed a bug in keeping removed entity object in the L2 cache. Fixed orphan removal of owner entity object in ... Fixed the behavior of CacheStoreMode setting in L2 shared cache. Fixed  TreeSet and TreeMap  element ...



The PersistenceManagerFactory is the interface to use to obtain PersistenceManager instances.(Interface of JDO)