User Guide - Apache OpenJPA - The Apache Software

405 Pages·2013·3.16 MB·English

Apache OpenJPA 2.0 User's Guide
Apache OpenJPA 2.0 User's Guide

1.Introduction ............................................................................................................................................. 1
1.About ............................................................................................................................................. 3
2.Legal .............................................................................................................................................. 4
2.1.License ................................................................................................................................ 4
2.2.Notice .................................................................................................................................. 4
2.3.Copyrights ............................................................................................................................ 4
2.3.1.Apache ...................................................................................................................... 4
2.3.2.Serp .......................................................................................................................... 4
2.3.3.Sun ........................................................................................................................... 4
2.3.4.Other ......................................................................................................................... 5
2.JavaPersistenceAPI ................................................................................................................................. 6
1.Introduction ....................................................................................................................................11
1.1.IntendedAudience.................................................................................................................11
1.2.LightweightPersistence ..........................................................................................................11
2.WhyJPA? ......................................................................................................................................12
3.JavaPersistenceAPIArchitecture .......................................................................................................14
3.1.JPAExceptions.....................................................................................................................15
4.Entity ............................................................................................................................................17
4.1.RestrictionsonPersistentClasses .............................................................................................18
4.1.1.DefaultorNo-ArgConstructor ......................................................................................18
4.1.2.Final ........................................................................................................................18
4.1.3.IdentityFields ............................................................................................................18
4.1.4.VersionField .............................................................................................................18
4.1.5.Inheritance ................................................................................................................19
4.1.6.PersistentFields .........................................................................................................19
4.1.7.Conclusions ...............................................................................................................20
4.2.EntityIdentity ......................................................................................................................20
4.2.1.IdentityClass .............................................................................................................21
4.2.1.1.IdentityHierarchies ..........................................................................................22
4.3.LifecycleCallbacks ...............................................................................................................23
4.3.1.CallbackMethods .......................................................................................................23
4.3.2.UsingCallbackMethods ..............................................................................................24
4.3.3.UsingEntityListeners .................................................................................................24
4.3.4.EntityListenersHierarchy ............................................................................................25
4.4.Conclusions .........................................................................................................................26
5.Metadata ........................................................................................................................................27
5.1.ClassMetadata .....................................................................................................................28
5.1.1.Entity .......................................................................................................................28
5.1.2.IdClass.....................................................................................................................29
5.1.3.MappedSuperclass .....................................................................................................29
5.1.4.Embeddable ...............................................................................................................29
5.1.5.EntityListeners ...........................................................................................................30
5.1.6.Example ...................................................................................................................30
5.2.FieldandPropertyMetadata ....................................................................................................31
5.2.1.ExplicitAccess...........................................................................................................32
5.2.2.Transient ...................................................................................................................33
5.2.3.Id.............................................................................................................................34
5.2.4.GeneratedValue .........................................................................................................34
5.2.5.EmbeddedId .............................................................................................................35
5.2.6.Version .....................................................................................................................35
5.2.7.Basic ........................................................................................................................35
5.2.7.1.FetchType ......................................................................................................36
5.2.8.Embedded .................................................................................................................36
5.2.9.ManyToOne.............................................................................................................36
5.2.9.1.CascadeType ..................................................................................................37
5.2.10.OneToMany ...........................................................................................................38
5.2.10.1.BidirectionalRelations ....................................................................................39
5.2.11.OneToOne .............................................................................................................39
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5.2.12.ManyToMany .........................................................................................................40
5.2.13.OrderBy .................................................................................................................41
5.2.14.MapKey .................................................................................................................41
5.2.15.PersistentFieldDefaults .............................................................................................41
5.3.XMLSchema .......................................................................................................................42
5.4.Conclusion...........................................................................................................................60
6.Persistence .....................................................................................................................................65
6.1.persistence.xml .....................................................................................................................65
6.2.Non-EEUse .........................................................................................................................70
7.EntityManagerFactory ......................................................................................................................71
7.1.ObtaininganEntityManagerFactory..........................................................................................71
7.2.ObtainingEntityManagers ......................................................................................................71
7.3.PersistenceContext ...............................................................................................................72
7.3.1.TransactionPersistenceContext ....................................................................................72
7.3.2.ExtendedPersistenceContext........................................................................................73
7.4.RetrievingPropertiesInformation.............................................................................................74
7.5.ClosingtheEntityManagerFactory............................................................................................74
7.6.PersistenceUnitUtil ................................................................................................................74
8.EntityManager ................................................................................................................................76
8.1.TransactionAssociation..........................................................................................................76
8.2.EntityLifecycleManagement ..................................................................................................77
8.3.LifecycleExamples ...............................................................................................................80
8.4.EntityIdentityManagement ....................................................................................................82
8.5.CacheManagement ...............................................................................................................82
8.6.QueryFactory ......................................................................................................................83
8.7.RetrievingPropertiesInformation.............................................................................................84
8.8.Closing ...............................................................................................................................84
9.Transaction.....................................................................................................................................85
9.1.TransactionTypes .................................................................................................................85
9.2.TheEntityTransactionInterface ...............................................................................................86
10.JPAQuery ....................................................................................................................................88
10.1.JPQLAPI ..........................................................................................................................88
10.1.1.QueryBasics ............................................................................................................88
10.1.2.RelationTraversal .....................................................................................................91
10.1.3.EmbeddableTraversal................................................................................................92
10.1.4.FetchJoins...............................................................................................................93
10.1.5.JPQLFunctions ........................................................................................................93
10.1.6.PolymorphicQueries .................................................................................................95
10.1.7.QueryParameters ......................................................................................................95
10.1.8.QueryHints .............................................................................................................96
10.1.8.1.LockingHints ................................................................................................96
10.1.8.2.LockTimeoutHint .........................................................................................97
10.1.8.3.QueryTimeoutHint ........................................................................................97
10.1.8.4.ResultSetSizeHint ........................................................................................97
10.1.8.5.IsolationLevelHint ........................................................................................97
10.1.8.6.OtherFetchplanHints......................................................................................97
10.1.8.7.Database-SpecificHints ...................................................................................97
10.1.8.8.NamedQueryHints ........................................................................................98
10.1.8.9.HandlingofMultipleSimilarQueryHints ...........................................................98
10.1.9.Ordering..................................................................................................................98
10.1.10.Aggregates .............................................................................................................99
10.1.11.NamedQueries .......................................................................................................99
10.1.12.DeleteByQuery ...................................................................................................100
10.1.13.UpdateByQuery ..................................................................................................100
10.2.JPQLLanguageReference ..................................................................................................101
10.2.1.JPQLStatementTypes .............................................................................................101
10.2.1.1.JPQLSelectStatement ..................................................................................101
10.2.1.2.JPQLUpdateandDeleteStatements ................................................................102
10.2.2.JPQLAbstractSchemaTypesandQueryDomains ........................................................102
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10.2.2.1.JPQLEntityNaming .....................................................................................102
10.2.2.2.JPQLSchemaExample..................................................................................102
10.2.3.JPQLFROMClauseandNavigationalDeclarations.......................................................103
10.2.3.1.JPQLFROMIdentifiers .................................................................................104
10.2.3.2.JPQLIdentificationVariables .........................................................................107
10.2.3.3.JPQLRangeDeclarations...............................................................................108
10.2.3.4.JPQLPathExpressions ..................................................................................108
10.2.3.5.JPQLJoins ..................................................................................................110
10.2.3.5.1.JPQLInnerJoins(RelationshipJoins) ....................................................111
10.2.3.5.2.JPQLOuterJoins ...............................................................................111
10.2.3.5.3.JPQLFetchJoins ...............................................................................112
10.2.3.6.JPQLCollectionMemberDeclarations .............................................................112
10.2.3.7.JPQLFROMClauseandSQL.........................................................................113
10.2.3.8.JPQLPolymorphism .....................................................................................113
10.2.4.JPQLWHEREClause .............................................................................................113
10.2.5.JPQLConditionalExpressions...................................................................................114
10.2.5.1.JPQLLiterals...............................................................................................114
10.2.5.2.JPQLIdentificationVariables .........................................................................114
10.2.5.3.JPQLPathExpressions ..................................................................................115
10.2.5.4.JPQLInputParameters ..................................................................................115
10.2.5.4.1.JPQLPositionalParameters .................................................................115
10.2.5.4.2.JPQLNamedParameters .....................................................................115
10.2.5.5.JPQLConditionalExpressionComposition .......................................................115
10.2.5.6.JPQLOperatorsandOperatorPrecedence .........................................................116
10.2.5.7.JPQLComparisonExpressions........................................................................116
10.2.5.8.JPQLBetweenExpressions ............................................................................117
10.2.5.9.JPQLInExpressions .....................................................................................118
10.2.5.10.JPQLLikeExpressions ................................................................................118
10.2.5.11.JPQLNullComparisonExpressions ...............................................................119
10.2.5.12.JPQLEmptyCollectionComparisonExpressions .............................................119
10.2.5.13.JPQLCollectionMemberExpressions ............................................................120
10.2.5.14.JPQLExistsExpressions ..............................................................................120
10.2.5.15.JPQLAllorAnyExpressions ........................................................................121
10.2.5.16.JPQLSubqueries ........................................................................................121
10.2.6.JPQLScalarExpressions ..........................................................................................122
10.2.6.1.ArithmeticExpressions ..................................................................................122
10.2.6.2.String,Arithmetic,andDatetimeFunctionalExpressions .....................................122
10.2.6.2.1.JPQLStringFunctions ........................................................................123
10.2.6.2.2.JPQLArithmeticFunctions ..................................................................123
10.2.6.2.3.JPQLDatetimeFunctions ....................................................................124
10.2.6.3.CaseExpressions ..........................................................................................124
10.2.6.4.EntityTypeExpressions ................................................................................125
10.2.7.JPQLGROUPBY,HAVING ....................................................................................125
10.2.8.JPQLSELECTClause .............................................................................................126
10.2.8.1.JPQLResultTypeoftheSELECTClause .........................................................127
10.2.8.2.JPQLConstructorExpressions ........................................................................128
10.2.8.3.JPQLNullValuesintheQueryResult ..............................................................129
10.2.8.4.JPQLEmbeddablesintheQueryResult ............................................................129
10.2.8.5.JPQLAggregateFunctions .............................................................................129
10.2.8.5.1.JPQLAggregateExamples ..................................................................130
10.2.8.5.2.JPQLNumericExpressionsintheSELECTClause ..................................130
10.2.9.JPQLORDERBYClause.........................................................................................131
10.2.10.JPQLBulkUpdateandDelete .................................................................................132
10.2.11.JPQLNullValues..................................................................................................133
10.2.12.JPQLEqualityandComparisonSemantics .................................................................134
10.2.13.JPQLBNF ...........................................................................................................134
11.JPACriteria ................................................................................................................................138
11.1.ConstructingaCriteriaQuery ...............................................................................................138
11.2.ExecutingaCriteriaQuery ...................................................................................................139
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11.3.ExtensiontoCriteriaAPI ....................................................................................................139
11.4.GenerationofCanonicalMetaModelclasses ...........................................................................139
12.SQLQueries ...............................................................................................................................141
12.1.CreatingSQLQueries ........................................................................................................141
12.2.RetrievingPersistentObjectswithSQL .................................................................................141
13.MappingMetadata .......................................................................................................................143
13.1.Table...............................................................................................................................143
13.2.UniqueConstraints ............................................................................................................146
13.3.Column ...........................................................................................................................147
13.4.IdentityMapping ...............................................................................................................147
13.5.Generators........................................................................................................................150
13.5.1.SequenceGenerator .................................................................................................150
13.5.2.TableGenerator .......................................................................................................151
13.5.3.Example ................................................................................................................152
13.6.Inheritance .......................................................................................................................153
13.6.1.SingleTable ...........................................................................................................154
13.6.1.1.Advantages .................................................................................................155
13.6.1.2.Disadvantages ..............................................................................................155
13.6.2.Joined ...................................................................................................................155
13.6.2.1.Advantages .................................................................................................157
13.6.2.2.Disadvantages ..............................................................................................157
13.6.3.TablePerClass .......................................................................................................157
13.6.3.1.Advantages .................................................................................................158
13.6.3.2.Disadvantages ..............................................................................................159
13.6.4.PuttingitAllTogether .............................................................................................159
13.7.Discriminator....................................................................................................................162
13.8.FieldMapping ..................................................................................................................166
13.8.1.BasicMapping .......................................................................................................166
13.8.1.1.LOBs .........................................................................................................166
13.8.1.2.Enumerated .................................................................................................167
13.8.1.3.TemporalTypes ...........................................................................................167
13.8.1.4.TheUpdatedMappings ..................................................................................167
13.8.2.SecondaryTables ....................................................................................................172
13.8.3.EmbeddedMapping.................................................................................................173
13.8.4.DirectRelations ......................................................................................................176
13.8.5.JoinTable ..............................................................................................................178
13.8.6.BidirectionalMapping .............................................................................................181
13.8.7.MapMapping .........................................................................................................181
13.9.TheCompleteMappings .....................................................................................................182
14.Conclusion .................................................................................................................................191
3.ReferenceGuide ....................................................................................................................................192
1.Introduction ..................................................................................................................................199
1.1.IntendedAudience...............................................................................................................199
2.Configuration................................................................................................................................200
2.1.Introduction .......................................................................................................................200
2.2.RuntimeConfiguration .........................................................................................................200
2.3.CommandLineConfiguration ...............................................................................................200
2.3.1.CodeFormatting.......................................................................................................201
2.4.PluginConfiguration............................................................................................................202
2.5.OpenJPAProperties .............................................................................................................203
2.5.1.openjpa.AutoClear ....................................................................................................203
2.5.2.openjpa.AutoDetach ..................................................................................................203
2.5.3.openjpa.BrokerFactory...............................................................................................204
2.5.4.openjpa.BrokerImpl ..................................................................................................204
2.5.5.openjpa.Callbacks .....................................................................................................204
2.5.6.openjpa.ClassResolver ...............................................................................................204
2.5.7.openjpa.Compatibility ...............................................................................................205
2.5.8.openjpa.ConnectionDriverName ..................................................................................205
2.5.9.openjpa.Connection2DriverName ................................................................................205
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2.5.10.openjpa.ConnectionFactory .......................................................................................205
2.5.11.openjpa.ConnectionFactory2 .....................................................................................206
2.5.12.openjpa.ConnectionFactoryName ...............................................................................206
2.5.13.openjpa.ConnectionFactory2Name .............................................................................206
2.5.14.openjpa.ConnectionFactoryMode ...............................................................................206
2.5.15.openjpa.ConnectionFactoryProperties .........................................................................207
2.5.16.openjpa.ConnectionFactory2Properties........................................................................207
2.5.17.openjpa.ConnectionPassword ....................................................................................207
2.5.18.openjpa.Connection2Password ..................................................................................207
2.5.19.openjpa.ConnectionProperties ...................................................................................208
2.5.20.openjpa.Connection2Properties ..................................................................................208
2.5.21.openjpa.ConnectionURL ..........................................................................................208
2.5.22.openjpa.Connection2URL.........................................................................................208
2.5.23.openjpa.ConnectionUserName...................................................................................208
2.5.24.openjpa.Connection2UserName .................................................................................209
2.5.25.openjpa.ConnectionRetainMode ................................................................................209
2.5.26.openjpa.DataCache..................................................................................................209
2.5.27.openjpa.DataCacheManager ......................................................................................209
2.5.28.openjpa.DataCacheMode ..........................................................................................210
2.5.29.openjpa.DataCacheTimeout ......................................................................................210
2.5.30.openjpa.DetachState ................................................................................................210
2.5.31.openjpa.DynamicDataStructs.....................................................................................210
2.5.32.openjpa.FetchBatchSize ...........................................................................................211
2.5.33.openjpa.EncryptionProvider ......................................................................................211
2.5.34.openjpa.FetchGroups ...............................................................................................211
2.5.35.openjpa.FlushBeforeQueries .....................................................................................211
2.5.36.openjpa.IgnoreChanges ............................................................................................212
2.5.37.openjpa.Id..............................................................................................................212
2.5.38.openjpa.InitializeEagerly ..........................................................................................212
2.5.39.openjpa.InverseManager...........................................................................................212
2.5.40.openjpa.LockManager..............................................................................................213
2.5.41.openjpa.LockTimeout ..............................................................................................213
2.5.42.openjpa.Log ...........................................................................................................213
2.5.43.openjpa.ManagedRuntime ........................................................................................213
2.5.44.openjpa.Mapping ....................................................................................................214
2.5.45.openjpa.MaxFetchDepth...........................................................................................214
2.5.46.openjpa.MetaDataFactory .........................................................................................214
2.5.47.openjpa.MetaDataRepository.....................................................................................214
2.5.48.openjpa.Multithreaded .............................................................................................215
2.5.49.openjpa.Optimistic ..................................................................................................215
2.5.50.openjpa.OrphanedKeyAction.....................................................................................215
2.5.51.openjpa.NontransactionalRead...................................................................................215
2.5.52.openjpa.NontransactionalWrite ..................................................................................216
2.5.53.openjpa.ProxyManager ............................................................................................216
2.5.54.openjpa.QueryCache................................................................................................216
2.5.55.openjpa.QueryCompilationCache ...............................................................................216
2.5.56.openjpa.ReadLockLevel ...........................................................................................216
2.5.57.openjpa.RemoteCommitProvider................................................................................217
2.5.58.openjpa.RestoreState ...............................................................................................217
2.5.59.openjpa.RetainState .................................................................................................217
2.5.60.openjpa.RetryClassRegistration .................................................................................217
2.5.61.openjpa.RuntimeUnenhancedClasses ..........................................................................218
2.5.62.openjpa.DynamicEnhancementAgent ..........................................................................218
2.5.63.openjpa.SavepointManager .......................................................................................218
2.5.64.openjpa.Sequence....................................................................................................219
2.5.65.openjpa.Specification ...............................................................................................219
2.5.66.openjpa.TransactionMode .........................................................................................219
2.5.67.openjpa.WriteLockLevel ..........................................................................................219
2.6.OpenJPAJDBCProperties ....................................................................................................220
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2.6.1.openjpa.jdbc.ConnectionDecorators .............................................................................220
2.6.2.openjpa.jdbc.DBDictionary ........................................................................................220
2.6.3.openjpa.jdbc.DriverDataSource ...................................................................................220
2.6.4.openjpa.jdbc.EagerFetchMode ....................................................................................221
2.6.5.openjpa.jdbc.FetchDirection .......................................................................................221
2.6.6.openjpa.jdbc.JDBCListeners .......................................................................................221
2.6.7.openjpa.jdbc.LRSSize................................................................................................221
2.6.8.openjpa.jdbc.MappingDefaults ....................................................................................222
2.6.9.openjpa.jdbc.MappingFactory .....................................................................................222
2.6.10.openjpa.jdbc.QuerySQLCache ...................................................................................222
2.6.11.openjpa.jdbc.ResultSetType ......................................................................................222
2.6.12.openjpa.jdbc.Schema ...............................................................................................222
2.6.13.openjpa.jdbc.SchemaFactory .....................................................................................223
2.6.14.openjpa.jdbc.Schemas ..............................................................................................223
2.6.15.openjpa.jdbc.SQLFactory .........................................................................................223
2.6.16.openjpa.jdbc.SubclassFetchMode ...............................................................................223
2.6.17.openjpa.jdbc.SynchronizeMappings ............................................................................224
2.6.18.openjpa.jdbc.TransactionIsolation ..............................................................................224
2.6.19.openjpa.jdbc.UpdateManager ....................................................................................224
2.6.20.CompatibilitywithSpecification ................................................................................224
3.Logging .......................................................................................................................................226
3.1.LoggingChannels ...............................................................................................................226
3.2.OpenJPALogging ...............................................................................................................227
3.3.DisablingLogging ...............................................................................................................228
3.4.Log4J................................................................................................................................228
3.5.ApacheCommonsLogging ...................................................................................................228
3.5.1.JDKjava.util.logging.................................................................................................229
3.6.CustomLog .......................................................................................................................229
4.JDBC ..........................................................................................................................................231
4.1.UsingtheOpenJPADataSource .............................................................................................231
4.2.UsingaThird-PartyDataSource .............................................................................................231
4.2.1.ManagedandXADataSources ....................................................................................232
4.3.RuntimeAccesstoDataSource ..............................................................................................233
4.4.DatabaseSupport ................................................................................................................234
4.4.1.DBDictionaryProperties ............................................................................................235
4.4.2.FirebirdDictionaryProperties ......................................................................................243
4.4.3.MySQLDictionaryProperties ......................................................................................243
4.4.4.OracleDictionaryProperties ........................................................................................244
4.4.5.SybaseDictionaryProperties .......................................................................................244
4.4.6.DelimitedIdentifiersSupport ......................................................................................244
4.5.SettingtheTransactionIsolation ............................................................................................245
4.6.SettingtheSQLJoinSyntax ..................................................................................................246
4.7.AccessingMultipleDatabases ...............................................................................................246
4.8.ConfiguringtheUseofJDBCConnections...............................................................................246
4.9.StatementBatching..............................................................................................................248
4.10.LargeResultSets...............................................................................................................249
4.11.DefaultSchema .................................................................................................................251
4.12.SchemaReflection .............................................................................................................251
4.12.1.SchemasList ..........................................................................................................252
4.12.2.SchemaFactory ......................................................................................................252
4.13.SchemaTool ....................................................................................................................253
4.14.XMLSchemaFormat .........................................................................................................255
5.PersistentClasses...........................................................................................................................258
5.1.PersistentClassList .............................................................................................................258
5.2.Enhancement ......................................................................................................................258
5.2.1.EnhancingatBuildTime ............................................................................................259
5.2.2.EnhancingJPAEntitiesonDeployment ........................................................................260
5.2.3.EnhancingatRuntime................................................................................................260
5.2.4.EnhancingDynamicallyatRuntime .............................................................................261
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5.2.5.OmittingtheOpenJPAenhancer ..................................................................................261
5.3.ManagedInterfaces .............................................................................................................262
5.4.ObjectIdentity ....................................................................................................................263
5.4.1.DatastoreIdentity .....................................................................................................263
5.4.2.EntitiesasIdentityFields ...........................................................................................264
5.4.3.ApplicationIdentityTool ...........................................................................................265
5.4.4.Autoassign/IdentityStrategyCaveats ..........................................................................266
5.5.ManagedInverses ...............................................................................................................267
5.6.PersistentFields ..................................................................................................................268
5.6.1.RestoringState .........................................................................................................268
5.6.2.TypingandOrdering .................................................................................................268
5.6.3.CalendarFieldsandTimeZones...................................................................................269
5.6.4.Proxies ...................................................................................................................269
5.6.4.1.SmartProxies ................................................................................................269
5.6.4.2.LargeResultSetProxies ..................................................................................269
5.6.4.3.CustomProxies..............................................................................................270
5.6.4.4.Serialization ..................................................................................................271
5.6.5.Externalization .........................................................................................................271
5.6.5.1.ExternalValues .............................................................................................274
5.7.FetchGroups ......................................................................................................................274
5.7.1.CustomFetchGroups ................................................................................................275
5.7.2.CustomFetchGroupConfiguration ..............................................................................276
5.7.3.Per-fieldFetchConfiguration ......................................................................................277
5.7.4.ImplementationNotes................................................................................................278
5.8.EagerFetching....................................................................................................................278
5.8.1.ConfiguringEagerFetching ........................................................................................279
5.8.2.EagerFetchingConsiderationsandLimitations ..............................................................280
6.Metadata ......................................................................................................................................281
6.1.MetadataFactory ................................................................................................................281
6.2.MetadataRepository ............................................................................................................282
6.3.AdditionalJPAMetadata ......................................................................................................282
6.3.1.DatastoreIdentity .....................................................................................................282
6.3.2.SurrogateVersion .....................................................................................................282
6.3.3.PersistentFieldValues...............................................................................................282
6.3.4.PersistentCollectionFields.........................................................................................283
6.3.5.PersistentMapFields ................................................................................................283
6.4.MetadataExtensions ............................................................................................................284
6.4.1.ClassExtensions.......................................................................................................284
6.4.1.1.FetchGroups .................................................................................................284
6.4.1.2.DataCache ...................................................................................................284
6.4.1.3.DetachedState ...............................................................................................284
6.4.2.FieldExtensions .......................................................................................................285
6.4.2.1.Dependent ....................................................................................................285
6.4.2.2.LoadFetchGroup ..........................................................................................285
6.4.2.3.LRS .............................................................................................................285
6.4.2.4.Inverse-Logical ..............................................................................................285
6.4.2.5.Read-Only ....................................................................................................285
6.4.2.6.Type ............................................................................................................286
6.4.2.7.Externalizer...................................................................................................286
6.4.2.8.Factory.........................................................................................................286
6.4.2.9.ExternalValues .............................................................................................286
6.4.3.Example .................................................................................................................287
7.Mapping ......................................................................................................................................288
7.1.ForwardMapping ................................................................................................................288
7.1.1.UsingtheMappingTool ............................................................................................289
7.1.2.GeneratingDDLSQL ................................................................................................290
7.1.3.RuntimeForwardMapping .........................................................................................290
7.2.ReverseMapping ................................................................................................................291
7.2.1.CustomizingReverseMapping ....................................................................................293
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