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release

2.3.6

Release date: 2012-01-09 Download (5.38 MB) Binary:  objectdb-2.3.6.zip You should start by following a  tutorial or reading the manual ...

 
forum_thread

Navigation to Collection Elements

Greetings ObjectDB team, Suppose I have a collection typed field (list/map/set...) in my persistent object of class X. Can I navigate (as oppose to using JOIN) to individual elements (in JPA & JDO) ? e.g.: x.list.get(10) x.map.get("key") x.list.get(10).get("key") // the element itself is a map Thanks & Best Regards... expressions (by using JPA's JOIN or JDO's contains). The array expressions that you wrote are not supported in ...

 
manual

Database Replication and Clustering

Replication enables maintaining up to date version of an ObjectDB database on multiple nodes.... ) ; A composite url contains two or more database urls separated by '|' . Usually only ...

 
forum_thread

Listing large number of complicated objects with paging.

Hi, For last few hours I was working on a problem with bad performance and memory problems with such a simple query: select prod from Product prod order by prod.id ASC Right now I have 55541 'Product' (attached to this post) entities in database and I'm trying to speed listing them with paging. The problem is, that running code that looks like this: ... I was trying to build wrapper object ProductTO that contains only fields that I need in listing and the use new ProductTO() in ...

 
forum_thread

Check for index existence ?

Hello, Is there a simple way to check if indexes specified in entities are well taken into account by ObjectDb ? Regards, Xirt #1 2016-08-06 16:09 Hello, Is there a simple way to check if indexes specified in entities are well taken into account by Obj ...

 
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. ... does its own evaluation. Every cached result entry contains query request (key) + query result (value). ObjectDB evaluated only ...

 
manual

JPA Query Structure (JPQL / Criteria)

Explains the structure of a JPQL query, which consists of 6 clauses: SELECT, FROM, WHERE, GROUP BY, HAVING, ORDER BY.... Organization of this Section This section contains the following pages: SELECT clause (JPQL / Criteria API) ...

 
forum_thread

Great product - needs better marketing - more popularity

Hi, ObjectDB! While you have a very nice product, which I recommend everywhere I go, it is quite difficult to explain to my customers what is it and why we should use it, and things like that, because it's quite unknown.  It's a great product, therefore I'm building the 3rd product based on ObjectDB since the beginning of this year, but I think it would be much better if your db was more popular. #1 2013-07-16 07:06 Hi, ObjectDB! While you have a very nice product, which I recommend everywhere I go, it is quite difficul ...

 
forum_thread

Dirty checking

Hi, wondering if anyone knows the best way to detect which objects have been changed in the database. ie: which objects, and which collections of objects, have been dirtied.     #1 2017-01-30 07:41 Hi, wondering if anyone knows the best way to detect which objects have been changed in the database. ie: ...

 
manual

ORDER BY clause (JPQL / Criteria API)

Explains how to use the ORDER BY clause in a JPA/JPQL query.... always the last in the query processing chain. If a query contains both an ORDER BY clause and a GROUP BY clause the SELECT clause ...