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issue

Unexpected exception (Error 990) on find

I have a huge amount of inserts/updates and after a about 850.000 Entities I got the following error: ... Unexpected exception in page #203864 entry #2: null Index Errors ------------ [1] Index local.jpa.entity.ebene1a.MyEntity[assignment] requires rebuild. - has ...

 
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About ObjectDB Database

ObjectDB is a powerful object oriented database management system (ODBMS). It is compact, reliable, easy to use and extremely fast. ObjectDB Object Database ObjectDB is a powerful object-oriented database management system (ODBMS). It is compact, reliable, easy to use and extremely fast. ObjectDB provides all the standard database management services (storage and ret ...

 
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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 ?... be slower than other comparison operators. An index on the string field could help. LIKE against patterns that start with ...

 
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ObjectDB Full-Text Search

Is there any way to perform a Full-Text Search using ObjectDB and Lucene or something similar? If so, how? Are there any examples available? #1 2014-03-06 16:41 Is there any way to perform a Full-Text Search using ObjectDB and Lucene or something similar? If so, how ...

 
issue

Best practice for history tracking

We would like to add to records start and end timestamp fields. When end field is null, it indicates the last version of this item. Few questions: ... field? If using end field, would an index matter? what is the best way to intercept the update ...

 
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persitencia (Preguntas y respuestas)

1ra.pregunta:     tengo un formulario y cuando grabo mas de un registro, solo me grava el ultimo mas no los anteriores. 2da.Pregunta:    Tengo un indice que no es el ID y necesito que mi tabla muestre los datos de acuerdo al indice. Como                          puedo hacerlo?. Alguien me sugiere algo. Gracias   #1 2015-08-06 19:46 1ra.pregunta: tengo un formulario y Cuando Grabo mas de un registro, solo me graba el ultimo pero no los anterior ...

 
manual

Numbers in JPQL and Criteria Queries

Shows how numbers, arithmetic expressions and numeric functions and operators (MOD, ABS) can be used in JPQL queries.... functions - when the return value is numeric, e.g. INDEX, SIZE. as string functions - when the return value is ...

 
issue

Large query parameter - out of memory

I have an entity object composed of an id, large data in the form of a string and the hashcode of the string as an index. The attached test saves 2000 of these objects, writing the data to a txt file as it goes. It then loops through the data from the file and queries for the entity id based on the data hashcode and the data itself. ... the form of a string and the hashcode of the string as an index. The attached test saves 2000 of these objects, writing the data to a txt ...

 
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JPA vs JDO - which is more efficient for OneToMany queries?

I'm curious about the trade offs between JDO and JPA. Seems to me that JDO will perform better and be statically typed. For example: Assume there are Customers and Orders.... hit? ie: with the JDO version you have essentially an index from the Customer class to its Orders, while with the JPA version you ...

 
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Query to search for common elements in two separate collections.

I'm trying to work out the most efficient way to build a query that can compare two collections for identical members. Something like: "SELECT o FROM Object o WHERE o.someCollection CONTAINS MEMBER OF :someCollection" Is something like this possible in the JPA spec? #1 2013-01-12 10:42 I'm trying to work out the most efficient way to build a query that can compare two collections for identical ...