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Issue with DISTINCT Select

It is getting more and more frustrating :( We've introduced distinct select instead of regular selection in our code (no changes else) and suddenly receive invalid identifiers in queries exceptions in various queries. Here's the stacktrace: ... Invalid order expression '$3' for distinct results at com.objectdb.o.MSG.d(MSG.java:61) at ... the query is invalid because you are trying to order the results based on a field of $2 - after eliminating $2 from the results. Notice that if profile is a collection then the same $1 value may ...

 
manual

JPA Query API

Describes the API that JPA provides for running queries against the database.... result type is unknown or when a query returns polymorphic results and the lowest known common denominator of all the result objects is ... It is easier to run queries and process the query results in a type safe manner when using the TypedQuery interface. ...

 
release

2.6.6

... in handling large objects with long primary keys as query results ( issue #260 ). Fixed detachment of embedded objects to ... Fixed a bug of returning managed hollow objects in query results. Fixed an error message for invalid DELETE query ( issue ...

 
forum_thread

Caching/Paging 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 set and hold the results 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 ?... their result sets. If I query the first set and hold the results in memory somehow, would that speed up the execution of the second ... (the EntityManager L1 cache) but instantiation of the results (if they contain entity objects) are slightly faster if relevant ...

 
manual

Logical Operators in JPQL and Criteria API

Explains how to use AND, OR and NOT in JPQL queries. Logical operators in JPQL and in JPA criteria queries enable composition of complex JPQL boolean expressions out of simple JPQL boolean expressions. This page covers the following topics: Logical Operators ...

 
forum_thread

Explorer in 2.3

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 data and Strings. After playing with it for a while, here is a list of additional features I'd love to have: 1. Export of selected data: a. Simple - Select a range of cells or a column header and copy text to the clipboard or save to a file (csv, html, etc..). (There appear to be copy menu options, but I cannot get them to work.) ... way to do ad-hoc JPQL queries and navigate through the results and even make small changes to primitive data and Strings. ... 3. On the Query page, please add a checkbox to request the Results either as a table or tree. 4. It would be terrific if the ...

 
api-jpa

javax.persistence.SqlResultSetMapping

Specifies the mapping of the result of a native SQL query.(Annotation of JPA)

 
manual

JPA Named Queries

Explains how to define and how to run JPA named queries.... embedding literals dynamically into the query string and results in more efficient queries. This page covers the following ... , Country. class ) ; List<Country> results = query. getResultList getResultList() TypedQuery's ...

 
forum_thread

Should derived fields of an EmbeddedId be manually maintained by app code?

If I have an Entity which has a primary key which is derived and I am implementing it using @EmbeddedId, am I responsible for maintaining the derived fields of the @EmbeddedId? I could not find anything in the JPA 2.0 spec http://download.oracle.com/auth/otn-pub/jcp/persistence-2.0-fr-oth-JSpec/persistence-2_0-final-spec.pdf?e=1317047713&h=54831c176e81a244a4c309e13eba0b27 which tells me what to expect. #1 2011-09-26 15:26 If I have an Entity which has a primary key which is derived and I am implementing it using @EmbeddedId, am I res ...

 
release

2.6.7

... in handling large objects with long primary keys as query results ( issue #260 ). Fixed detachment of embedded objects to ... Fixed a bug of returning managed hollow objects in query results. Fixed an error message for invalid DELETE query ( issue ...