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EntityManager JPA or JDO impl and different behavior

Hi, I have an issue with the EntityManager. My persistance XML looks like: <?xml version="1.0" encoding="UTF-8"?> <persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"> ... an issue with the EntityManager. My persistance XML looks like: <?xml version = "1.0" encoding = "UTF-8" ?> ... manually in the transaction due to lack of time but would like to get to the bottom of LAZY/EAGER loading of maps.   ...

 
issue

Typo in ObjectDB 1.0 Manual

Support > Knowledge Base > ObjectDB 1.0 Manual > Chapter 7 "JDOQL Queries" > Section 7.2 "Query Filter Syntax" > Subsection "Fields" > Second to last sentence Remove "not" from that sentence.   "An attempt to access a field or invoke a method using a null reference results in a false evaluation for the containing expression but no exception is not thrown."   ... Thank you.   Looks like there is also a quoting issue on the query.setFilter() line in section 7.5 ... Just incase it is browser related, here is what it looks like for me ... (see attachment)     ...

 
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Optimization of Map Queries

hi! I am having loads and loads of occurrences of something like ((com.test.MyEntity) $1.map.get('com.test.MyEntity')).someProperty ... ((com.test.MyEntity) $1.map.get('com.test.MyEntity')).someOtherProperty .. ((com.test.MyEntity) $1.map.get('com.test.MyEntity')).someMoreProperties I need to use full qualified names for casting as well as for the map keys because same entity simple names may occur multiple times. Now I've got two questions: ... I am having loads and loads of occurrences of something like ( ( com . test . MyEntity ) $1 . map . ... Hi, How would such a join variable look like? And how to create it using criteria api? We do have heavy usage ...

 
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how explorer queries work

i'm curious as to how the explorer is able to execute queries when its obviously not aware of the object model that i built. the reason is because i have an application where i want to be able to execute somewhat generalized queries and i won't know what classes are in the object model ahead of time. this is especially curious to me in client-server mode since the .jar with the object model classes is on the server side, not the client side where explorer is running. ... entities. (obviously the explorer must be doing something like this; correct me if i'm wrong.) is this part of the public interface ... ( ) ; throws an exception like this: ...

 
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Composite indexes

Hi, I read your manual about defining Indexes for JPA Entities (http://www.objectdb.com/java/jpa/entity/index), but I still have some problems understanding how and when should I use them.   Let's start with some example then. Assume we have an entity that represents an interior design image, called Inspiration : ... field that returns the smallest subset of unique records (like for example "isPublished" which is either true or false, then "room" which ... same field as secondary member in many @Indexes? Something like that : @ Index ( members = { ...

 
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removed objects stay with null field values in the reference

We have a class with a one to many relationship declared like this (1 or more objects of the same class are linked into the relationship, no circular referencing): ... We have a class with a one to many relationship declared like this (1 or more objects of the same class are linked into the ... But you may still have broken references to that object, like links to a web page that doesn't exist. ...

 
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ObjectDB Object Database Features

ObjectDB provides a rich set of features, many of them as the result of supporting the JPA and JDO APIs.... SQL like (but object based) query language - familiar to most developers. ... JPQL - Java Persistence (JPA) Query Language - SQL like syntax. JDOQL - Java Data ...

 
manual

[ODB1] Chapter 1 - About ObjectDB

Describes the main features and editions of ObjectDB 1.0 for Java/JDO.... you. You can even run your application on small devices like PocketPC (if Java is installed), because ObjectDB has a very small ... explore, query and edit the database content visually, is like developing software without a debugger. 1.2  ObjectDB Operating ...

 
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Some technical questions

Hi, ObjectDB looks interesting. Have two technical questions... (1) what locking model does ObjectDB use? I.e. 2PL or MVCC? Do writers block readers? Do readers block writers? (2) what's the recommended usage for SAAS? One ObjectDB database per customer, or one ObjectDB database for all? Thank you, Andrej ... implements online backups, does it implement something like MVCC, so it can see the data at the time the backup was started (to have ... implements online backups, does it implement something like MVCC, so it can see the data at the time the backup was started (to have ...

 
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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... // the element itself is a map How about arrays like x.array[1] and x.array[1][2] ? Thanks & Best Regards ... it to be done in JPA/JDO queries. How about arrays like x.array[1] and x.array[1][2] ? If such navigations in ...