ObjectDB Database Search

are assigned as arguments. Path expressions that navigate from one object to another. Instances of user ... . But more often they are used in JPQL path expressions that navigate to values of simple types (number, boolean ... , and they can be used in ordering . Navigation through Path Expressions A path expression always starts

;persistent object of class X. Can I  navigate  (as opposed to using JOIN) to  ... Regards geekox86 Mohannad AlAwad Yes, you can navigate from any managed entity object to any ... it to be done in JPA/JDO queries. How about arrays like x.array[1] and x.array[1][2] ? If such navigations

Greetings ObjectDB team, Suppose I pass a List of persistent objects to some query as a parameter, can I navigate to those objects' fields ? E.g.: SELECT x FROM ClassX x WHERE x.a IS MEMBER OF :y.b Thank You ! geekox86 Mohannad AlAwad You cannot navigate from a collection of objects

Hello, I need to evaluate a field ("identifier") which is situated in a collection, within an entity. As stated in the documentation it is not possible to navigate there with the dot operator since its a collection. Is it there a way to evaluate this field? Here is the query, the entity

Pre-detach loading: retrieval by navigation not working in if statement

after retrieval by a special automatic query. Note : Navigation through inverse fields is much less efficient than navigation  through ordinary persistent fields, since it requires running queries. Inverse ... relationships is usually much more efficient (unless navigation in the inverse direction is rare

navigation through non collection and map persistent fields are also retrieved. Theoretically, in some ... instances are also retrieved automatically. Retrieval by Navigation and Access All the persistent ... of all the persistent fields. As seen, the entire graph of objects is available for navigation

activation (no activation depth) - objects are retrieved from the database automatically by navigating ... Expressions Path navigation expressions using the dot (.) operator. Comparison operators (

windows provide easier navigation . Because every reference between two database objects is represented by a parent-child relationship in the tree, you can navigate among objects by expanding nodes in

the following operators (in order of decreasing precedence): Navigation operator (.) Arithmetic operators ... , ...). Paths, navigation and types ( get , type ). Arithmetic expressions ( sum , diff , prod

of transparent navigation and fetch  makes it very easy to use, since it provides the illusion that all the database objects are available in memory for navigation . But this feature

for managed entity objects, including transparent navigation to other database objects, transparent update ... are missing the JPA functionality of managed entity objects (e.g. transparent navigation

). Retrieval by navigation from detached objects is not supported, so only persistent fields

of entity objects that are reachable from that object by navigation through persistent reference fields

Numeric values may appear in JPQL queries in many forms: as  numeric literals - e.g. 123 , -12.5 . as parameters - when numeric values are assigned as arguments. as  path expressions - in navigation to persistent numeric fields. as aggregate expressions - e.g. COUNT. as collection

Collections may appear in JPQL queries: as parameters - when collections are assigned as arguments. as  path expressions - in navigation to persistent collection fields. IS [NOT] EMPTY The IS [NOT] EMPTY operator checks whether a specified collection is empty or not. For example: c.languages

String values may appear in JPQL queries in various forms: as  string literals - e.g. 'abc' , ''. as parameters - when string values are assigned as arguments. as  path expressions - in navigation to persistent string fields. as results of predefined JPQL string manipulation functions

, navigation and types ( get , type ). Arithmetic expressions ( sum , diff , prod , quot , mod , abs

Date and time expressions may appear in JPQL queries: as date and time literals - e.g. {d '2011-12-31'} , {t '23:59:59'} . as parameters - when date and time values are assigned as arguments. as  path expressions - in navigation to persistent date and time fields. as results of predefined

A main limitation of detached objects (as explained on the Detached Entities manual page) is: Retrieval by navigation from detached objects is not supported, so only persistent fields ... for that) but for us the inability to navigate lazy relationships of detached entities is a big showstopper, as we rely

is invalid. You cannot navigate through collections in JPQL directly. You have to use JOIN to define ... Support of direct navigation from collections (with no JOIN) was just added in build 2.2.4_02 ... to JPQL using a hint the following exception is thrown on attempt to use the new navigation from

to explore database objects visually, navigate among them and execute queries is very valuable ... advantage of using the browser window is in navigation among objects. Because every reference between two database objects is represented by a parent-child relationship in the tree, you can navigate

in the [ Navigator ] window and selecting Report Run Report :  

project: Right click the Reports node in the [ Navigator ] and select New Report . Enter the report

/entity/fields#Inverse_Fields . A query will still be executed (i.e. navigation from Customer to Order ... above, which is less efficient in ORM-based implementation and requires a JOIN table and a query for navigation ... Moshal It depends on what your application does, of course. But assuming that navigation

be aware that navigation from the mapped by (inverse) side to the owner side is slower ... ;relationships (with no mapped by). You will have to maintain both sides, but navigation may be faster since no queries will be required. This ability (of navigation in the to many direction with no queries

; Then one can navigate to Classes, double click "byte[]" to view its instances, click "Compute retained sizes ... , one can navigate the selected JdoBlob2 object's reference listing in JavaVisualVm to discover which object(s ... ; Using the heap dump I navigate through a lot of unrecognizable stuff under there (all presumably

in object databases, because navigation in the database can easily start from them, as explained in ... it can be retrieved simply by navigating through the persistent fields ... navigation from a reachable object using persistent fields is also reachable. On every run

First, the new Explorer in ObjectDB is fantastic! This is exactly what we've needed - an easy way to do ad-hoc JPQL queries and navigate through the results and even make small changes to primitive ... that are opened while navigating the results. My initial result might have only a few records

and then navigate to each element separately, each navigation requires a separate round trip

expression in JPQL because  messageList is a List and navigation from a list must be done by an additional variable. ObjectDB supports navigation from lists as an extension, so the following query

.PersistenceException Navigation from 'java.util.Calendar' through 'DAY_OF_WEEK' is invalid (error 763) at com ... .run(EventDispatchThread.java:91) Caused by: com.objectdb.o.UserException: Navigation from 'java.util

" is considered as a string literal value rather than as a navigation expression), and because this constant

find and by navigation (and not in queries). You may try the following undocumented ObjectDB query

The associated feature request is:  Navigation through lazy loading from Detached Objects   webel Dr Darren Kelly

baURI is a byte[]; JP QL select e.baURI.length from URI e where id=82778 JP QL [ObjectDB 2.2.9_04] javax.persistence.PersistenceException Navigation from 'byte[]' through 'length' is invalid (error 763) at com.objectdb.jpa.JpaQuery.getResultList(JpaQuery.java:636) at util.JPQLcmd.QureyCMD(JPQLcmd

. The ability to navigate through persistent references transparently, loading necessary objects

users, but mainly for storage and retrieval or navigation , and rarely in queries. Actually support

the rest are just ORs, no?? Alex quasado Alexander Adam Maybe this is the result of navigation through null in one of the OR components.  Navigation should be compiled as LEFT OUTER JOIN to avoid losing ... component that causes this query execution failure? Does it have navigation through null

The new Explorer of ObjectDB 2 supports retrieval of database objects by classes and navigation . Retrieval of database objects by executing queries visually should also be supported. This is one of the features that have been supported by the old Explorer of ObjectDB 1. It has been temporarily

Added support of navigation through collections  (as a JPQL extension). Added version display to the Server and Explorer About dialog boxes. Fixed an UPDATE/DELETE query bug in client-server mode. Fixed an ArrayIndexOutOfBoundsException in retrieval of large objects. Fixed Explorer display

the quotes I've found confirming that EclipseLink permits navigation of lazy loaded relationships

Fixed a critical bug in extensive removal operations of large objects. Improved the performance of navigation through an inverse (mapped by) field if the owner field is indexed. Fixed a LEFT OUTER JOIN bug . Fixed a bug in parsing queries with parenthesis followed by NOT . Fixed a bug in running

me bi-directional navigation of my entities, even though I am only managing a reference

navigation through a broken reference (probably a reference to a deleted object) during query execution

doesn't handle well queries with a lot of variables, and complex navigation (e.g.  $1.postalAddresses

a result of path navigation (e.g. x.a.b ). Only explicit variables are shown in toString

calls as non-standard extensions. Navigation through a null -valued field, which would throw ... for inclusion in the result set. Navigation through multi-valued fields ( Collection types) is specified ... the element of the collection being evaluated. Navigation through single-valued fields is specified by

. Navigation through a null -valued field, which would throw NullPointerException , is treated as ... . Navigation through multi-valued fields ( Collection types) is specified using a variable declaration ... being evaluated. Navigation through single-valued fields is specified by the Java language syntax of field

". The field must be declared in the candidate class or must be a navigation expression starting