About primary key

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Manual
28

Defining a JPA Entity Class

for persistent fields, how to define and use a primary key and what a version field is and how to use it. If you are already familiar with JPA you might have noticed that the Point entity class has no primary key ... defined primary key is not required. On the other hand, ObjectDB also supports explicit JPA primary
Manual
27

JPA Entity Fields

(Mapped By) fields Primary key (ID) fields Version field The first three groups (transient, persistent ... two groups (primary key and version fields) can only be used in entity classes. Primary key fields are discussed in the Primary Key section. Transient Fields Transient entity fields are fields
Manual
26

Index Definition

field (similar to how primary keys behave). @Index represents either an ordinary index ... can only be defined on ordinary persistent fields (not on primary key / version fields). Composite Index A composite ... the BTree's primary sort key and which field is used as a secondary sort key. If x is specified first
Forum
26

problem when primary key value is zero

and recommendations, in particular there are some primary keys with value == 0. These cause problems for objectDB, typically "JPA Unexpected argument as primary key". When using eclipselink, there is a workaround ... have a zero value in primary key column -->            
Forum
26

A bidirectional OneToOne association with a shared primary key

@OneToOne association that has a shared primary key, example: http://fruzenshtein.com/bidirectional-one-to-one-primary-key-association/ Can ObjectDB support this same specific relationship ... one to one association, but it cannot be based on identical primary keys, i.e. the primary key
Forum
26

More Efficient Primary Keys

Primary Key  with two Longs b) Embedded Primary Key with two Longs c) Furthermore, as String ... it is a composite primary key with the same size and structure. (b) requires instantiation ... Can you give us a recommendation as we can represent the Key (UUID) most efficient? Both in terms
Forum
25

Intermittent: "Attempt to reuse an existing primary key value" when persisting a new instance

Hi,   I don't have a useful test case to expose this issue, but I am getting an intermittent "Attempt to reuse an existing primary key value". In this particular instance, the error is: Attempt to reuse an existing primary key value (com.x.y.z.UserPassword:1) (error 642) at com.objectdb.jpa
Forum
25

Merge failure with composite primary key

it. The composite primary key issue is unclear, since switching to a single primary key field doesn't seem to make any difference. eurojet
Forum
25

Merge Issue: Attempt to reuse an existing primary key value

: Attempt to reuse an existing primary key value (MyTestCase$MyEntityChild:'child1') at com.objectdb.o ... that "Attempt to reuse an existing primary key value" on my merge operation is a total nonsense. If 2.5
Forum
25

Primary key generation problem after changing entity package

keep getting errors : Attempt to reuse an existing primary key value... My primary keys are annotated