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83

Detaching objects after JOIN FETCH

Hi, I have a question about detaching objects after issuing query with JOIN FETCH. Let's say I ... to fetch all B classes with all A classes skipping lazy loading: select b from B b join fetch b ... is closed, B.aClasses is always null. I thought, that after join fetch and CascadeType.DETACH list
83

LEFT (OUTER) JOIN problem when mappedBy is defined

this query: "SELECT i FROM Invoice i LEFT OUTER JOIN i.itemList items" But this query never returns ... JOIN works correctly. Is this normal behaviour? Thank you Michael Sample application public class ... Invoice i LEFT OUTER JOIN i.itemList items"); List resultList = query.getResultList
82

"Problem" with cross join

=InheritanceType.JOINED) ... @ManyToOne private CI ci; subclass CIstring private String text; I ... primary key fields in JOIN queries). Please try the new build (2.0.4_01) that should fix the bug
80

joining of tables

Hi In objectdb site i found :Note: This ORM/SQL annotation is silently ignored by ObjectDB so i want join tow table and generate a third table. Ex: table 1: employee table 2: address and the generate table will be table 3: emp_add employee: e_id, e_name address: add_id, city, house
16

Index Definition

query above, the index order should be x first and y second. Indexes on collections are useful in JOIN queries: SELECT d FROM Document d JOIN d.words w WHERE w = 'JPA' The Document entity class ... can also be used for executing the following query: SELECT d FROM Document d JOIN d.words w
16

Mapped by fields are not initialized by JOIN FETCH in queries

As demonstrated in this forum thread, a mapped by collection field with lazy fetch mode is not initialized in results of a query that uses JOIN FETCH on that collection field (when enhancement is used). support Support Build 2.4.1_06 fixes this issue (fields are now initialized and the test in
13

javax.persistence.JoinColumn

a column for joining an entity association or element collection. If the JoinColumn annotation itself is defaulted, a single join column is assumed and the default values apply. Example: @ManyToOne ... @JoinColumn(name="CUST_ID") // join column is in table for Order public Set
11

javax.persistence.MapKeyJoinColumn

) Specifies a mapping to an entity that is a map key. The map key join column is in the collection table, join table, or table of the target entity that is used to represent the map. If no MapKeyJoinColumn annotation is specified, a single join column is assumed and the default values apply. Example 1
9

JPA Queries

variables, join and fetch): Other criteria query expressions (for all the query clauses):
1

[ODB1] Chapter 7 - JDOQL Queries

as a replacement for the JOIN operation of SQL Support of bound variables is mandatory, but support ... by ObjectDB, but considered optional by JDO. Queries with unbound variables are similar to JOIN ... like JOIN queries in SQL, queries with unbound variables may become very slow, so caution is needed

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