Datastore Definition

datanucleus.ConnectionURL
Description	URL specifying the datastore to use for persistence. Note that this will define the type of datastore as well as the datastore itself. Please refer to the datastores guides for the URL appropriate for the type of datastore you're using.
Range of Values

datanucleus.ConnectionUserName
Description	Username to use for connecting to the DB
Range of Values

datanucleus.ConnectionPassword
Description	Password to use for connecting to the DB. See datanucleus.ConnectionPasswordDecrypter for a way of providing an encrypted password here
Range of Values

datanucleus.ConnectionDriverName
Description	The name of the (JDBC) driver to use for the DB (for RDBMS only).
Range of Values

datanucleus.ConnectionFactory
Description	Instance of a connection factory for transactional connections. This is an alternative to datanucleus.ConnectionURL. For RDBMS, it must be an instance of javax.sql.DataSource. See Data Sources.
Range of Values

datanucleus.ConnectionFactory2
Description	Instance of a connection factory for nontransactional connections. This is an alternative to datanucleus.ConnectionURL. For RDBMS, it must be an instance of javax.sql.DataSource. See Data Sources.
Range of Values

datanucleus.ConnectionFactoryName
Description	The JNDI name for a connection factory for transactional connections. For RBDMS, it must be a JNDI name that points to a javax.sql.DataSource object. See Data Sources.
Range of Values

datanucleus.ConnectionFactory2Name
Description	The JNDI name for a connection factory for nontransactional connections. For RBDMS, it must be a JNDI name that points to a javax.sql.DataSource object. See Data Sources.
Range of Values

datanucleus.ConnectionPasswordDecrypter
Description	Name of a class that implements org.datanucleus.store.connection.DecryptionProvider and should only be specified if the password is encrypted in the persistence properties
Range of Values

General

datanucleus.IgnoreCache
Description	Whether to ignore the cache for queries. If the user sets this to true then the query will evaluate in the datastore, but the instances returned will be formed from the datastore; this means that if an instance has been modified and its datastore values match the query then the instance returned will not be the currently cached (updated) instance, instead an instance formed using the datastore values.
Range of Values	true | false

datanucleus.Multithreaded
Description	Whether to run the PM/EM multithreaded. Note that this is a hint only to try to allow thread-safe operations on the PM/EM
Range of Values	true | false

datanucleus.NontransactionalRead
Description	Whether to allow nontransactional reads
Range of Values	false | true

datanucleus.NontransactionalWrite
Description	Whether to allow nontransactional writes
Range of Values	false | true

datanucleus.Optimistic
Description	Whether to use optimistic transactions (JDO, JPA). For JDO this defaults to false and for JPA it defaults to true
Range of Values	true | false

datanucleus.RetainValues
Description	Whether to suppress the clearing of values from persistent instances on transaction completion. With JDO this defaults to false, whereas for JPA it is true
Range of Values	true | false

datanucleus.RestoreValues
Description	Whether persistent object have transactional field values restored when transaction rollback occurs.
Range of Values	true | false

datanucleus.Mapping
Description	Name for the ORM MetaData mapping files to use with this PMF. For example if this is set to "mysql" then the implementation looks for MetaData mapping files called "{classname}-mysql.orm" or "package-mysql.orm". If this is not specified then the JDO implementation assumes that all is specified in the JDO MetaData file.
Range of Values

datanucleus.mapping.Catalog
Description	Name of the catalog to use by default for all classes persisted using this PMF/EMF. This can be overridden in the MetaData where required, and is optional. DataNucleus will prefix all table names with this catalog name if the RDBMS supports specification of catalog names in DDL. RDBMS datastores only
Range of Values

datanucleus.mapping.Schema
Description	Name of the schema to use by default for all classes persisted using this PMF/EMF. This can be overridden in the MetaData where required, and is optional. DataNucleus will prefix all table names with this schema name if the RDBMS supports specification of schema names in DDL. RDBMS datastores only
Range of Values

datanucleus.tenantId
Description	String id to use as a discriminator on all persistable class tables to restrict data for the tenant using this application instance (aka multi-tenancy via discriminator). RDBMS, MongoDB datastores only
Range of Values

datanucleus.DetachAllOnCommit
Description	Allows the user to select that when a transaction is committed all objects enlisted in that transaction will be automatically detached.
Range of Values	true | false

datanucleus.detachAllOnRollback
Description	Allows the user to select that when a transaction is rolled back all objects enlisted in that transaction will be automatically detached.
Range of Values	true | false

datanucleus.CopyOnAttach
Description	Whether, when attaching a detached object, we create an attached copy or simply migrate the detached object to attached state
Range of Values	true | false

datanucleus.allowAttachOfTransient
Description	When you call EM.merge with a transient object (with PK fields set), if you enable this feature then it will first check for existence of an object in the datastore with the same identity and, if present, will merge into that object (rather than just trying to persist a new object). The default for JDO is false, and for JPA is true.
Range of Values	true | false

datanucleus.attachSameDatastore
Description	When attaching an object DataNucleus by default assumes that you're attaching to the same datastore as you detached from. DataNucleus does though allow you to attach to a different datastore (for things like replication). Set this to false if you want to attach to a different datastore to what you detached from
Range of Values	true | false

datanucleus.detachAsWrapped
Description	When detaching, any mutable second class objects (Collections, Maps, Dates etc) are typically detached as the basic form (so you can use them on client-side of your application). This property allows you to select to detach as wrapped objects. It only works with "detachAllOnCommit" situations (not with detachCopy) currently
Range of Values	true | false

datanucleus.DetachOnClose
Description	This allows the user to specify whether, when a PM/EM is closed, that all objects in the L1 cache are automatically detached. Users are recommended to use the datanucleus.DetachAllOnCommit wherever possible. This will not work in JCA mode.
Range of Values	false | true

datanucleus.detachmentFields
Description	When detaching you can control what happens to loaded/unloaded fields of the FetchPlan. The default for JDO is to load any unloaded fields of the current FetchPlan before detaching. You can also unload any loaded fields that are not in the current FetchPlan (so you only get the fields you require) as well as a combination of both options
Range of Values	load-fields | unload-fields | load-unload-fields

datanucleus.maxFetchDepth
Description	Specifies the default maximum fetch depth to use for fetching operations. The JDO spec defines a default of 1, meaning that only the first level of related objects will be fetched by default. The JPA spec doesn't provide fetch group control, just a "default fetch group" type concept, consequently the default there is -1 currently.
Range of Values	-1 | 1 | positive integer (non-zero)

datanucleus.detachedState
Description	Allows control over which mechanism to use to determine the fields to be detached. By default DataNucleus uses the defined "fetch-groups". Obviously JPA1/JPA2 don't have that (although it is an option with DataNucleus), so we also allow loaded which will detach just the currently loaded fields, and all which will detach all fields of the object (be careful with this option since it, when used with maxFetchDepth of -1 will detach a whole object graph!)
Range of Values	fetch-groups | all | loaded

datanucleus.TransactionType
Description	Type of transaction to use. If running under JavaSE the default is RESOURCE_LOCAL, and if running under JavaEE the default is JTA.
Range of Values	RESOURCE_LOCAL | JTA

datanucleus.ServerTimeZoneID
Description	Id of the TimeZone under which the datastore server is running. If this is not specified or is set to null it is assumed that the datastore server is running in the same timezone as the JVM under which DataNucleus is running.
Range of Values

datanucleus.PersistenceUnitName
Description	Name of a persistence-unit to be found in a persistence.xml file (under META-INF) that defines the persistence properties to use and the classes to use within the persistence process.
Range of Values

datanucleus.PersistenceUnitLoadClasses
Description	Used when we have specified the persistence-unit name for a PMF/EMF and where we want the datastore "tables" for all classes of that persistence-unit loading up into the StoreManager. Defaults to false since some databases are slow so such an operation would slow down the startup process.
Range of Values	true | false

datanucleus.persistenceXmlFilename
Description	URL name of the persistence.xml file that should be used instead of using "META-INF/persistence.xml".
Range of Values

datanucleus.datastoreReadTimeout
Description	The timeout to apply to all reads (millisecs). e.g by query or by PM.getObjectById(). Only applies if the underlying datastore supports it
Range of Values	0 | A positive value (MILLISECONDS)

datanucleus.datastoreWriteTimeout
Description	The timeout to apply to all writes (millisecs). e.g by makePersistent, or by an update. Only applies if the underlying datastore supports it
Range of Values	0 | A positive value (MILLISECONDS)

datanucleus.singletonPMFForName
Description	Whether to only allow a singleton PMF for a particular name (the name can be either the name of the PMF in jdoconfig.xml, or the name of the persistence-unit). If a subsequent request is made for a PMF with a name that already exists then a warning will be logged and the original PMF returned.
Range of Values	true | false

datanucleus.singletonEMFForName
Description	Whether to only allow a singleton EMF for persistence-unit. If a subsequent request is made for an EMF with a name that already exists then a warning will be logged and the original EMF returned.
Range of Values	true | false

datanucleus.allowListenerUpdateAfterInit
Description	Whether you want to be able to add/remove listeners on the JDO PMF after it is marked as not configurable (when the first PM is created). The default matches the JDO spec, not allowing changes to the listeners in use.
Range of Values	true | false

datanucleus.storeManagerType
Description	Type of the StoreManager to use for this PMF/EMF. This has typical values of "rdbms", "mongodb". If it isnt specified then it falls back to trying to find the StoreManager from the connection URL. The associated DataNucleus plugin has to be in the CLASSPATH when selecting this. When using data sources (as usually done in a JavaEE container), DataNucleus cannot find out the correct type automatically and this option must be set.
Range of Values	rdbms | mongodb | alternate StoreManager key

datanucleus.jmxType
Description	Which JMX server to use when hooking into JMX. Please refer to the Monitoring Guide
Range of Values	default | mx4j

datanucleus.deletionPolicy
Description	Allows the user to decide the policy when deleting objects. The default is "JDO2" which firstly checks if the field is dependent and if so deletes dependents, and then for others will null any foreign keys out. The problem with this option is that it takes no account of whether the user has also defined <foreign-key> elements, so we provide a "DataNucleus" mode that does the dependent field part first and then if a FK element is defined will leave it to the FK in the datastore to perform any actions, and otherwise does the nulling.
Range of Values	JDO2 | DataNucleus

datanucleus.identityStringTranslatorType
Description	You can allow identities input to pm.getObjectById(id) be translated into valid JDO ids if there is a suitable translator. See Identity String Translator Plugin
Range of Values

datanucleus.identityKeyTranslatorType
Description	You can allow identities input to pm.getObjectById(cls, key) be translated into valid JDO ids if there is a suitable key translator. See Identity Key Translator Plugin
Range of Values

datanucleus.datastoreIdentityType
Description	Which "datastore-identity" class plugin to use to represent datastore identities. Refer to Datastore Identity extensions for details.
Range of Values	datanucleus | kodo | xcalia | {user-supplied plugin}

datanucleus.executionContext.maxIdle
Description	Specifies the maximum number of ExecutionContext objects that are pooled ready for use
Range of Values	20 | integer value greater than 0

datanucleus.executionContext.reaperThread
Description	Whether to start a reaper thread that continually monitors the pool of ExecutionContext objects and frees them off after they have surpassed their expiration period
Range of Values	false | true

datanucleus.objectProvider.className
Description	Class name for the ObjectProvider to use when managing object state. The default for RDBMS is ReferentialStateManagerImpl, and is StateManagerImpl for all other datastores.
Range of Values	{user-provided class-name}

datanucleus.useImplementationCreator
Description	Whether to allow use of the implementation-creator (feature of JDO to dynamically create implementations of persistent interfaces). Defaults to true for JDO, and false for JPA
Range of Values	true | false

datanucleus.manageRelationships
Description	This allows the user control over whether DataNucleus will try to manage bidirectional relations, correcting the input objects so that all relations are consistent. This process runs when flush()/commit() is called. JDO defaults to true and JPA defaults to false You can set it to false if you always set both sides of a relation when persisting/updating.
Range of Values	true | false

datanucleus.manageRelationshipsChecks
Description	This allows the user control over whether DataNucleus will make consistency checks on bidirectional relations. If "datanucleus.managedRelationships" is not selected then no checks are performed. If a consistency check fails at flush()/commit() then a JDOUserException is thrown. You can set it to false if you want to omit all consistency checks.
Range of Values	true | false

datanucleus.persistenceByReachabilityAtCommit
Description	Whether to run the "persistence-by-reachability" algorithm at commit() time. This means that objects that were reachable at a call to makePersistent() but that are no longer persistent will be removed from persistence. For performance improvements, consider turning this off.
Range of Values	true | false

datanucleus.classLoaderResolverName
Description	Name of a ClassLoaderResolver to use in class loading. DataNucleus provides a default that loosely follows the JDO specification for class loading. This property allows the user to override this with their own class better suited to their own loading requirements.
Range of Values	datanucleus | {name of class-loader-resolver plugin}

datanucleus.primaryClassLoader
Description	Sets a primary classloader for situations where a primary classloader is not accessible. This ClassLoader is used when the class is not found in the default ClassLoader search path. As example, when the database driver is loaded by a different ClassLoader not in the ClassLoader search path for JDO or JPA specifications.
Range of Values	instance of java.lang.ClassLoader

datanucleus.plugin.pluginRegistryClassName
Description	Name of a class that acts as registry for plug-ins. This defaults to org.datanucleus.plugin.NonManagedPluginRegistry (for when not using OSGi). If you are within an OSGi environment you can set this to org.datanucleus.plugin.OSGiPluginRegistry
Range of Values	{fully-qualified class name}

datanucleus.plugin.pluginRegistryBundleCheck
Description	Defines what happens when plugin bundles are found and are duplicated
Range of Values	EXCEPTION | LOG | NONE

datanucleus.plugin.allowUserBundles
Description	Defines whether user-provided bundles providing DataNucleus extensions will be registered. This is only respected if used in a non-Eclipse OSGi environment.
Range of Values	true | false

datanucleus.plugin.validatePlugins
Description	Defines whether a validation step should be performed checking for plugin dependencies etc. This is only respected if used in a non-Eclipse OSGi environment.
Range of Values	false | true

datanucleus.findObject.validateWhenCached
Description	When a user calls getObjectById (JDO) or findObject (JPA) and they request validation this allows the turning off of validation when an object is found in the (L2) cache. Can be useful for performance reasons, but should be used with care. Defaults to true for JDO (to be consistent with the JDO spec), and to false for JPA.
Range of Values	true | false

datanucleus.findObject.typeConversion
Description	When calling PM.getObjectById(Class, Object) or EM.find(Class, Object) the second argument really ought to be the exact type of the primary-key field. This property enables conversion of basic numeric types (Long, Integer, Short) to the appropriate numeric type (if the PK is a numeric type). Set this to false if you want strict JPA compliance.
Range of Values	true | false

Schema Control

datanucleus.schema.autoCreateAll
Description	Whether to automatically generate any schema, tables, columns, constraints that don't exist. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.schema.autoCreateSchema
Description	Whether to automatically generate any schema that doesn't exist. This depends very much on whether the datastore in question supports this operation. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.schema.autoCreateTables
Description	Whether to automatically generate any tables that don't exist. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.schema.autoCreateColumns
Description	Whether to automatically generate any columns that don't exist. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.schema.autoCreateConstraints
Description	Whether to automatically generate any constraints that don't exist. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.autoCreateWarnOnError
Description	Whether to only log a warning when errors occur during the auto-creation/validation process. Please use with care since if the schema is incorrect errors will likely come up later and this will postpone those error checks til later, when it may be too late!!
Range of Values	true | false

datanucleus.schema.validateAll
Description	Alias for defining datanucleus.schema.validateTables, datanucleus.schema.validateColumns and datanucleus.schema.validateConstraints as all true. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.schema.validateTables
Description	Whether to validate tables against the persistence definition. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.schema.validateColumns
Description	Whether to validate columns against the persistence definition. This refers to the column detail structure and NOT to whether the column exists or not. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.schema.validateConstraints
Description	Whether to validate table constraints against the persistence definition. Please refer to the Schema Guide for more details.
Range of Values	true | false

datanucleus.readOnlyDatastore
Description	Whether the datastore is read-only or not (fixed in structure and contents).
Range of Values	true | false

datanucleus.readOnlyDatastoreAction
Description	What happens when a datastore is read-only and an object is attempted to be persisted.
Range of Values	EXCEPTION | IGNORE

datanucleus.generateSchema.database.mode
Description	Whether to perform any schema generation to the database at startup. Will process the schema for all classes that have metadata loaded at startup (i.e the classes specified in a persistence-unit).
Range of Values	create | drop | drop-and-create | none

datanucleus.generateSchema.scripts.mode
Description	Whether to perform any schema generation into scripts at startup. Will process the schema for all classes that have metadata loaded at startup (i.e the classes specified in a persistence-unit).
Range of Values	create | drop | drop-and-create | none

datanucleus.generateSchema.scripts.create.target
Description	Name of the script file to write to if doing a "create" with the target as "scripts"
Range of Values	datanucleus-schema-create.ddl | {filename}

datanucleus.generateSchema.scripts.drop.target
Description	Name of the script file to write to if doing a "drop" with the target as "scripts"
Range of Values	datanucleus-schema-drop.ddl | {filename}

datanucleus.generateSchema.scripts.create.source
Description	Name of a script file to run to create tables. Can be absolute filename, or URL string
Range of Values	{filename}

datanucleus.generateSchema.scripts.drop.source
Description	Name of a script file to run to drop tables. Can be absolute filename, or URL string
Range of Values	{filename}

datanucleus.generateSchema.scripts.load
Description	Name of a script file to run to load data into the schema. Can be absolute filename, or URL string
Range of Values	{filename}

datanucleus.identifierFactory
Description	Name of the identifier factory to use when generating table/column names etc (RDBMS datastores only). See also the JDO RDBMS Identifier Guide.
Range of Values	datanucleus1 | datanucleus2 | jpox | jpa | {user-plugin-name}

datanucleus.identifier.namingFactory
Description	Name of the identifier NamingFactory to use when generating table/column names etc (non-RDBMS datastores). Defaults to "datanucleus2" for JDO and "jpa" for JPA usage.
Range of Values	datanucleus2 | jpa | {user-plugin-name}

datanucleus.identifier.case
Description	Which case to use in generated table/column identifier names. See also the Datastore Identifier Guide. RDBMS defaults to UPPERCASE. Cassandra defaults to lowercase
Range of Values	UPPERCASE | LowerCase | MixedCase

datanucleus.identifier.wordSeparator
Description	Separator character(s) to use between words in generated identifiers. Defaults to "_" (underscore)

datanucleus.identifier.tablePrefix
Description	Prefix to be prepended to all generated table names (if the identifier factory supports it)

datanucleus.identifier.tableSuffix
Description	Suffix to be appended to all generated table names (if the identifier factory supports it)

datanucleus.defaultInheritanceStrategy
Description	How to choose the inheritance strategy default for classes where no strategy has been specified. With JDO2 this will be "new-table" for base classes and "superclass-table" for subclasses. With TABLE_PER_CLASS this will be "new-table" for all classes.
Range of Values	JDO2 | TABLE_PER_CLASS

datanucleus.store.allowReferencesWithNoImplementations
Description	Whether we permit a reference field (1-1 relation) or collection of references where there are no defined implementations of the reference. False means that an exception will be thrown during schema generation
Range of Values	true | false

Transactions and Locking

datanucleus.transactionIsolation
Description	Select the default transaction isolation level for ALL PM/EM factories. Some databases do not support all isolation levels, refer to your database documentation. Please refer to the transaction guides for JDO and JPA
Range of Values	read-uncommitted | read-committed | repeatable-read | serializable

datanucleus.SerializeRead
Description	With datastore transactions you can apply locking to objects as they are read from the datastore. This setting applies as the default for all PM/EMs obtained. You can also specify this on a per-transaction or per-query basis (which is often better to avoid deadlocks etc)
Range of Values	true | false

datanucleus.jtaLocator
Description	Selects the locator to use when using JTA transactions so that DataNucleus can find the JTA TransactionManager. If this isn't specified and using JTA transactions DataNucleus will search all available locators which could have a performance impact. See JTA Locator extension. If specifying "custom_jndi" please also specify "datanucleus.jtaJndiLocation"
Range of Values	jboss | jonas | jotm | oc4j | orion | resin | sap | sun | weblogic | websphere | custom_jndi | alias of a JTA transaction locator

datanucleus.jtaJndiLocation
Description	Name of a JNDI location to find the JTA transaction manager from (when using JTA transactions). This is for the case where you know where it is located. If not used DataNucleus will try certain well-known locations
Range of Values	JNDI location

datanucleus.datastoreTransactionFlushLimit
Description	For use when using datastore transactions and is the limit on number of dirty objects before a flush to the datastore will be performed.
Range of values	1 | positive integer

datanucleus.flush.mode
Description	Sets when persistence operations are flushed to the datastore. MANUAL means that operations will be sent only on flush()/commit(). AUTO means that operations will be sent immediately.
Range of values	MANUAL | AUTO

datanucleus.flush.optimised
Description	Whether to use an "optimised" flush process, changing the order of persists for referential integrity (as used by RDBMS typically), or whether to just build a list of deletes, inserts and updates and do them in batches. RDBMS defaults to true, whereas other datastores default to false (due to not having referential integrity, so gaining from batching
Range of values	true | false

datanucleus.nontx.atomic
Description	When a user invokes a nontransactional operation they can choose for these changes to go straight to the datastore (atomically) or to wait until either the next transaction commit, or close of the PM/EM. Disable this if you want operations to be processed with the next real transaction. This defaults to true for JDO, and false for JPA
Range of Values	true | false

datanucleus.connectionPoolingType
Description	This property allows you to utilise a 3rd party software package for enabling connection pooling. When using RDBMS you can select from DBCP, C3P0, Proxool, BoneCP, or dbcp-builtin. You must have the 3rd party jars in the CLASSPATH to use these options. Please refer to the Connection Pooling guide for details.
Range of Values	None | DBCP | DBCP2 | C3P0 | Proxool | BoneCP | HikariCP | dbcp-builtin | {others}

datanucleus.connectionPoolingType.nontx
Description	This property allows you to utilise a 3rd party software package for enabling connection pooling for nontransactional connections using a DataNucleus plugin. If you don't specify this value but do define the above value then that is taken by default. Refer to the above property for more details.
Range of Values	None | DBCP | DBCP2 | C3P0 | Proxool | BoneCP | HikariCP | "dbcp-builtin" | {others}

datanucleus.connection.nontx.releaseAfterUse
Description	Applies only to non-transactional connections and refers to whether to re-use (pool) the connection internally for later use. The default behaviour is to close any such non-transactional connection after use. If doing significant non-transactional processing in your application then this may provide performance benefits, but be careful about the number of connections being held open (if one is held open per PM/EM).
Range of Values	true | false

datanucleus.connection.singleConnectionPerExecutionContext
Description	With an ExecutionContext (PM/EM) we normally allocate one connection for a transaction and close it after the transaction, then a different connection for nontransactional ops. This flag acts as a hint to the store plugin to obtain and retain a single connection throughout the lifetime of the PM/EM.
Range of Values	true | false

datanucleus.connection.resourceType
Description	Resource Type for connection ???
Range of Values	JTA | RESOURCE_LOCAL

datanucleus.connection.resourceType2
Description	Resource Type for connection 2
Range of Values	JTA | RESOURCE_LOCAL

Caching

datanucleus.cache.collections
Description	SCO collections can be used in 2 modes in DataNucleus. You can allow DataNucleus to cache the collections contents, or you can tell DataNucleus to access the datastore for every access of the SCO collection. The default is to use the cached collection.
Range of Values	true | false

datanucleus.cache.collections.lazy
Description	When using cached collections/maps, the elements/keys/values can be loaded when the object is initialised, or can be loaded when accessed (lazy loading). The default is to use lazy loading when the field is not in the current fetch group, and to not use lazy loading when the field is in the current fetch group.
Range of Values	true | false

datanucleus.cache.level1.type
Description	Name of the type of Level 1 cache to use. Defines the backing map. See also Cache docs for JDO, and for JPA
Range of Values	soft | weak | strong | {your-plugin-name}

datanucleus.cache.level2.type
Description	Name of the type of Level 2 Cache to use. Can be used to interface with external caching products. Use "none" to turn off L2 caching. See also Cache docs for JDO, and for JPA
Range of Values	none | soft | weak | coherence | ehcache | ehcacheclassbased | cacheonix | oscache | swarmcache | javax.cache | spymemcached | xmemcached | {your-plugin-name}

datanucleus.cache.level2.mode
Description	The mode of operation of the L2 cache, deciding which entities are cached. The default (UNSPECIFIED) is the same as DISABLE_SELECTIVE. See also Cache docs for JDO, and for JPA
Range of Values	NONE | ALL | ENABLE_SELECTIVE | DISABLE_SELECTIVE | UNSPECIFIED

datanucleus.cache.level2.storeMode
Description	Whether to use the L2 cache for storing values (set to "bypass" to not store within the context of the operation)
Range of Values	use | bypass

datanucleus.cache.level2.retrieveMode
Description	Whether to use the L2 cache for retrieving values (set to "bypass" to not retrieve from L2 cache within the context of the operation, i.e go to the datastore)
Range of Values	use | bypass

datanucleus.cache.level2.updateMode
Description	When the objects in the L2 cache should be updated. Defaults to updating at commit AND when fields are read from a datastore object
Range of Values	commit-and-datastore-read | commit

datanucleus.cache.level2.cacheName
Description	Name of the cache. This is for use with plugins such as the Tangosol cache plugin for accessing the particular cache. Please refer to the Cache Guide for JDO or JPA
Range of Values	your cache name

datanucleus.cache.level2.maxSize
Description	Max size for the L2 cache (supported by weak, soft, coherence, ehcache, ehcacheclassbased, javax.cache)
Range of Values	-1 | integer value

datanucleus.cache.level2.clearAtClose
Description	Whether the close of the L2 cache (when the PMF/EMF closes) should also clear out any objects from the underlying cache mechanism. By default it will clear objects out but if the user has configured an external cache product and wants to share objects across multiple PMF/EMFs then this can be set to false.
Range of Values	true | false

datanucleus.cache.level2.batchSize
Description	When objects are added to the L2 cache at commit they are typically batched. This property sets the max size of the batch.
Range of Values	100 | integer value

datanucleus.cache.level2.timeout
Description	Some caches (Cacheonix, javax.cache) allow specification of an expiration time for objects in the cache. This property is the timeout in milliseconds (will be unset meaning use cache default).
Range of Values	-1 | integer value

datanucleus.cache.level2.readThrough
Description	With javax.cache L2 caches you can configure the cache to allow read-through
Range of Values	true | false

datanucleus.cache.level2.writeThrough
Description	With javax.cache L2 caches you can configure the cache to allow write-through
Range of Values	true | false

datanucleus.cache.level2.storeByValue
Description	With javax.cache L2 caches you can configure the cache to store by value (as opposed to by reference)
Range of Values	true | false

datanucleus.cache.level2.statisticsEnabled
Description	With javax.cache L2 caches you can configure the cache to enable statistics gathering (accessible via JMX)
Range of Values	false | true

datanucleus.cache.queryCompilation.type
Description	Type of cache to use for caching of generic query compilations
Range of Values	none | soft | weak | strong | {your-plugin-name}

datanucleus.cache.queryCompilationDatastore.type
Description	Type of cache to use for caching of datastore query compilations
Range of Values	none | soft | weak | strong | {your-plugin-name}

datanucleus.cache.queryResults.type
Description	Type of cache to use for caching query results.
Range of Values	none | soft | weak | strong | javax.cache | spymemcached | xmemcached | cacheonix | {your-plugin-name}

datanucleus.cache.queryResults.cacheName
Description	Name of cache for caching the query results.
Range of Values	datanucleus-query | {your-name}

datanucleus.cache.queryResults.maxSize
Description	Max size for the query results cache (supported by weak, soft, strong)
Range of Values	-1 | integer value

Validation

datanucleus.validation.mode
Description	Determines whether the automatic lifecycle event validation is in effect. Defaults to auto for JPA and none for JDO
Range of Values	auto | callback | none

datanucleus.validation.group.pre-persist
Description	The classes to validation on pre-persist callback
Range of Values

datanucleus.validation.group.pre-update
Description	The classes to validation on pre-update callback
Range of Values

datanucleus.validation.group.pre-remove
Description	The classes to validation on pre-remove callback
Range of Values

datanucleus.validation.factory
Description	The validation factory to use in validation
Range of Values

Value Generation

datanucleus.valuegeneration.transactionAttribute
Description	Whether to use the PM connection or open a new connection. Only used by value generators that require a connection to the datastore.
Range of Values	New | UsePM

datanucleus.valuegeneration.transactionIsolation
Description	Select the default transaction isolation level for identity generation. Must have datanucleus.valuegeneration.transactionAttribute set to New Some databases do not support all isolation levels, refer to your database documentation. Please refer to the transaction guides for JDO and JPA
Range of Values	read-uncommitted | read-committed | repeatable-read | serializable

datanucleus.valuegeneration.sequence.allocationSize
Description	If using JDO3.0 still and not specifying the size of your sequence, this acts as the default allocation size.
Range of Values	10 | (integer value)

datanucleus.valuegeneration.increment.allocationSize
Description	Sets the default allocation size for any "increment" value strategy. You can configure each member strategy individually but they fall back to this value if not set
Range of Values	10 | (integer value)

MetaData

datanucleus.metadata.jdoFileExtension
Description	Suffix for JDO MetaData files. Provides the ability to override the default suffix and also to have one PMF with one suffix and another with a different suffix, hence allowing differing persistence of the same classes using different PMF's.
Range of values	jdo | {file suffix}

datanucleus.metadata.ormFileExtension
Description	Suffix for ORM MetaData files. Provides the ability to override the default suffix and also to have one PMF with one suffix and another with a different suffix, hence allowing differing persistence of the same classes using different PMF's.
Range of values	orm | {file suffix}

datanucleus.metadata.jdoqueryFileExtension
Description	Suffix for JDO Query MetaData files. Provides the ability to override the default suffix and also to have one PMF with one suffix and another with a different suffix, hence allowing differing persistence of the same classes using different PMF's.
Range of values	jdoquery | {file suffix}

datanucleus.metadata.alwaysDetachable
Description	Whether to treat all classes as detachable irrespective of input metadata. See also "alwaysDetachable" enhancer option.
Range of values	false | true

datanucleus.metadata.ignoreMetaDataForMissingClasses
Description	Whether to ignore metadata for classes that aren't found. Default(false) is to throw an exception.
Range of values	false | true

datanucleus.metadata.xml.validate
Description	Whether to validate the MetaData file(s) for XML correctness (against the DTD) when parsing.
Range of values	true | false

datanucleus.metadata.xml.namespaceAware
Description	Whether to allow for XML namespaces in metadata files. The vast majority of sane people should not need this at all, but it's enabled by default to allow for those that do (since v3.2.3)
Range of values	true | false

datanucleus.metadata.allowXML
Description	Whether to allow XML metadata. Turn this off if not using any, for performance. From v3.0.4 onwards
Range of values	true | false

datanucleus.metadata.allowAnnotations
Description	Whether to allow annotations metadata. Turn this off if not using any, for performance. From v3.0.4 onwards
Range of values	true | false

datanucleus.metadata.allowLoadAtRuntime
Description	Whether to allow load of metadata at runtime. This is intended for the situation where you are handling persistence of a persistence-unit and only want the classes explicitly specified in the persistence-unit.
Range of values	true | false

datanucleus.metadata.autoregistration
Description	Whether to use the JDO auto-registration of metadata. Turned on by default
Range of values	true | false

datanucleus.metadata.supportORM
Description	Whether to support "orm" mapping files. By default we use what the datastore plugin supports. This can be used to turn it off when the datastore supports it but we dont plan on using it (for performance)
Range of values	true | false

Auto-Start

datanucleus.autoStartMechanism
Description	How to initialise DataNucleus at startup. This allows DataNucleus to read in from some source the classes that it was persisting for this data store the previous time. XML stores the information in an XML file for this purpose. SchemaTable (only for RDBMS) stores a table in the RDBMS for this purpose. Classes looks at the property datanucleus.autoStartClassNames for a list of classes. MetaData looks at the property datanucleus.autoStartMetaDataFiles for a list of metadata files The other option (default) is None (start from scratch each time). Please refer to the Auto-Start Mechanism Guide for more details. Alternatively just use persistence.xml to specify the classes and/or mapping files to load at startup. Note also that "Auto-Start" is for RUNTIME use only (not during SchemaTool).
Range of Values	None | XML | Classes | MetaData | SchemaTable

datanucleus.autoStartMechanismMode
Description	The mode of operation of the auto start mode. Currently there are 3 values. "Quiet" means that at startup if any errors are encountered, they are fixed quietly. "Ignored" means that at startup if any errors are encountered they are just ignored. "Checked" means that at startup if any errors are encountered they are thrown as exceptions.
Range of values	Checked | Ignored | Quiet

datanucleus.autoStartMechanismXmlFile
Description	Filename used for the XML file for AutoStart when using "XML" Auto-Start Mechanism

datanucleus.autoStartClassNames
Description	This property specifies a list of classes (comma-separated) that are loaded at startup when using the "Classes" Auto-Start Mechanism.

datanucleus.autoStartMetaDataFiles
Description	This property specifies a list of metadata files (comma-separated) that are loaded at startup when using the "MetaData" Auto-Start Mechanism.

Query control

datanucleus.query.flushBeforeExecution
Description	This property can enforce a flush to the datastore of any outstanding changes just before executing all queries. If using optimistic transactions any updates are typically held back until flush/commit and so the query would otherwise not take them into account.
Range of Values	true | false

datanucleus.query.useFetchPlan
Description	Whether to use the FetchPlan when executing a JDOQL query. The default is to use it which means that the relevant fields of the object will be retrieved. This allows the option of just retrieving the identity columns.
Range of Values	true | false

datanucleus.query.compileOptimised
Description	The generic query compilation process has a simple "optimiser" to try to iron out potential problems in users queries. It isn't very advanced yet, but currently will detect and try to fix a query clause like "var == this" (which is pointless). This will be extended in the future to handle other common situations
Range of Values	true | false

datanucleus.query.jdoql.allowAll
Description	javax.jdo.query.JDOQL queries are allowed by JDO only to run SELECT queries. This extension permits to bypass this limitation so that DataNucleus extension bulk "update" and bulk "delete" can be run.
Range of Values	false | true

datanucleus.query.sql.allowAll
Description	javax.jdo.query.SQL queries are allowed by JDO2 only to run SELECT queries. This extension permits to bypass this limitation (so for example can execute stored procedures).
Range of Values	false | true

datanucleus.query.checkUnusedParameters
Description	Whether to check for unused input parameters and throw an exception if found. The JDO and JPA specs require this check and is a good guide to having misnamed a parameter name in the query for example.
Range of Values	true | false

Datastore Specific

Properties below here are for particular datastores only.

datanucleus.rdbms.datastoreAdapterClassName
Description	This property allows you to supply the class name of the adapter to use for your datastore. The default is not to specify this property and DataNucleus will autodetect the datastore type and use its own internal datastore adapter classes. This allows you to override the default behaviour where there maybe is some issue with the default adapter class. Applicable for RDBMS only
Range of Values	(valid class name on the CLASSPATH)

datanucleus.rdbms.useLegacyNativeValueStrategy
Description	This property changes the process for deciding the value strategy to use when the user has selected "native"(JDO)/"auto"(JPA) to be like it was with version 3.0 and earlier, so using "increment" and "uuid-hex". Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.statementBatchLimit
Description	Maximum number of statements that can be batched. The default is 50 and also applies to delete of objects. Please refer to the Statement Batching guide Applicable for RDBMS only
Range of Values	integer value (0 = no batching)

datanucleus.rdbms.checkExistTablesOrViews
Description	Whether to check if the table/view exists. If false, it disables the automatic generation of tables that don't exist. Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.useDefaultSqlType
Description	This property applies for schema generation in terms of setting the default column "sql-type" (when you haven't defined it) and where the JDBC driver has multiple possible "sql-type" for a "jdbc-type". If the property is set to false, it will take the first provided "sql-type" from the JDBC driver. If the property is set to true, it will take the "sql-type" that matches what the DataNucleus "plugin.xml" implies. Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.initializeColumnInfo
Description	Allows control over what column information is initialised when a table is loaded for the first time. By default info for all columns will be loaded. Unfortunately some RDBMS are particularly poor at returning this information so we allow reduced forms to just load the primary key column info, or not to load any. Applicable for RDBMS only
Range of Values	ALL | PK | NONE

datanucleus.rdbms.classAdditionMaxRetries
Description	The maximum number of retries when trying to find a class to persist or when validating a class. Applicable for RDBMS only
Range of Values	3 | A positive integer

datanucleus.rdbms.constraintCreateMode
Description	How to determine the RDBMS constraints to be created. DataNucleus will automatically add foreign-keys/indices to handle all relationships, and will utilise the specified MetaData foreign-key information. JDO2 will only use the information in the MetaData file(s). Applicable for RDBMS only
Range of Values	DataNucleus | JDO2

datanucleus.rdbms.uniqueConstraints.mapInverse
Description	Whether to add unique constraints to the element table for a map inverse field. Possible values are true or false. Applicable for RDBMS only
Range of values	true | false

datanucleus.rdbms.discriminatorPerSubclassTable
Description	Property that controls if only the base class where the discriminator is defined will have a discriminator column Applicable for RDBMS only
Range of values	false | true

datanucleus.rdbms.stringDefaultLength
Description	The default (max) length to use for all strings that don't have their column length defined in MetaData. Applicable for RDBMS only
Range of Values	255 | A valid length

datanucleus.rdbms.stringLengthExceededAction
Description	Defines what happens when persisting a String field and its length exceeds the length of the underlying datastore column. The default is to throw an Exception. The other option is to truncate the String to the length of the datastore column. Applicable for RDBMS only
Range of Values	EXCEPTION | TRUNCATE

datanucleus.rdbms.useColumnDefaultWhenNull
Description	If an object is being persisted and a field (column) is null, the default behaviour is to look whether the column has a "default" value defined in the datastore and pass that in. You can turn this off and instead pass in NULL for the column by setting this property to false. Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.persistEmptyStringAsNull
Description	When persisting en empty string, should it be persisted as null in the datastore. This is to allow for datastores (Oracle) that dont differentiate between null and empty string. If it is set to false and the datastore doesnt differentiate then a special character will be saved when storing an empty string. Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.query.fetchDirection
Description	The direction in which the query results will be navigated. Applicable for RDBMS only
Range of Values	forward | reverse | unknown

datanucleus.rdbms.query.resultSetType
Description	Type of ResultSet to create. Note 1) Not all JDBC drivers accept all options. The values correspond directly to the ResultSet options. Note 2) Not all java.util.List operations are available for scrolling result sets. An Exception is raised when unsupported operations are invoked. Applicable for RDBMS only
Range of Values	forward-only | scroll-sensitive | scroll-insensitive

datanucleus.rdbms.query.resultSetConcurrency
Description	Whether the ResultSet is readonly or can be updated. Not all JDBC drivers support all options. The values correspond directly to the ResultSet options. Applicable for RDBMS only
Range of Values	read-only | updateable

datanucleus.rdbms.query.multivaluedFetch
Description	How any multi-valued field should be fetched in a query. 'exists' means use an EXISTS statement hence retrieving all elements for the queried objects in one SQL with EXISTS to select the affected owner objects. 'none' means don't fetch container elements. Applicable for RDBMS only
Range of Values	exists | none

datanucleus.rdbms.oracleNlsSortOrder
Description	Sort order for Oracle String fields in queries (BINARY disables native language sorting) Applicable for RDBMS only
Range of Values	LATIN | See Oracle documentation

datanucleus.rdbms.mysql.engineType
Description	Specify the default engine for any tables created in MySQL. Applicable to MySQL only
Range of Values	InnoDB | valid engine for MySQL

datanucleus.rdbms.mysql.collation
Description	Specify the default collation for any tables created in MySQL. Applicable to MySQL only
Range of Values	valid collation for MySQL

datanucleus.rdbms.mysql.characterSet
Description	Specify the default charset for any tables created in MySQL. Applicable to MySQL only
Range of Values	valid charset for MySQL

datanucleus.rdbms.schemaTable.tableName
Description	Name of the table to use when using auto-start mechanism of "SchemaTable" Please refer to the JDO Auto-Start guide Applicable for RDBMS only
Range of Values	NUCLEUS_TABLES | Valid table name

datanucleus.rdbms.connectionProviderName
Description	Name of the connection provider to use to allow failover Please refer to the Failover guide Applicable for RDBMS only
Range of Values	PriorityList | Name of a provider

datanucleus.rdbms.connectionProviderFailOnError
Description	Whether to fail if an error occurs, or try to continue and log warnings Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.dynamicSchemaUpdates
Description	Whether to allow dynamic updates to the schema. This means that upon each insert/update the types of objects will be tested and any previously unknown implementations of interfaces will be added to the existing schema. Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.omitDatabaseMetaDataGetColumns
Description	Whether to bypass all calls to DatabaseMetaData.getColumns(). This JDBC method is called to get schema information, but on some JDBC drivers (e.g Derby) it can take an inordinate amout of time. Setting this to true means that your datastore schema has to be correct and no checks will be performed. Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.sqlTableNamingStrategy
Description	Name of the plugin to use for defining the names of the aliases of tables in SQL statements. Applicable for RDBMS only
Range of Values	alpha-scheme | t-scheme

datanucleus.rdbms.tableColumnOrder
Description	How we should order the columns in a table. The default is to put the fields of the owning class first, followed by superclasses, then subclasses. An alternative is to start from the base superclass first, working down to the owner, then the subclasses Applicable for RDBMS only
Range of Values	owner-first | superclass-first

datanucleus.rdbms.allowColumnReuse
Description	This property allows you to reuse columns for more than 1 field of a class. It is false by default to protect the user from erroneously typing in a column name. Additionally, if a column is reused, the user ought to think about how to determine which field is written to that column ... all reuse ought to imply the same value in those fields so it doesn't matter which field is written there, or retrieved from there. Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.statementLogging
Description	How to log SQL statements. The default is to log the statement and replace any parameters with the value provided in angle brackets. Alternatively you can log the statement with any parameters replaced by just the values (no brackets). The final option is to log the raw JDBC statement (with ? for parameters). Applicable for RDBMS only
Range of Values	values-in-brackets | values | jdbc

datanucleus.rdbms.fetchUnloadedAutomatically
Description	If enabled will, upon a request to load a field, check for any unloaded fields that are non-relation fields or 1-1/N-1 fields and will load them in the same SQL call. Applicable for RDBMS only
Range of Values	true | false

datanucleus.rdbms.adapter.informixUseSerialForIdentity
Description	Whether we are using SERIAL for identity columns (instead of SERIAL8). Applicable for RDBMS only.
Range of Values	true | false

datanucleus.cloud.storage.bucket
Description	This is a mandatory property that allows you to supply the bucket name to store your data. Applicable for Google Storage, and AmazonS3 only.
Range of Values	Any valid string

datanucleus.hbase.enforceUniquenessInApplication
Description	Setting this property to true means that when a new object is persisted (and its identity is assigned), no check will be made as to whether it exists in the datastore and that the user takes responsibility for such checks. Applicable for HBase only.
Range of Values	true | false

datanucleus.cassandra.compression
Description	Type of compression to use for the Cassandra cluster. Applicable for Cassandra only.
Range of Values	none | snappy

datanucleus.cassandra.metrics
Description	Whether metrics are enabled for the Cassandra cluster. Applicable for Cassandra only.
Range of Values	true | false

datanucleus.cassandra.ssl
Description	Whether SSL is enabled for the Cassandra cluster. Applicable for Cassandra only.
Range of Values	true | false

datanucleus.cassandra.socket.readTimeoutMillis
Description	Socket read timeout for the Cassandra cluster. Applicable for Cassandra only.
Range of Values

datanucleus.cassandra.socket.connectTimeoutMillis
Description	Socket connect timeout for the Cassandra cluster. Applicable for Cassandra only.
Range of Values