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Marking a field with the @GeneratedValue annotation indicates that the field's value ... it for non-key numeric persistent fields. The following sections explain the available value generation ... a primary key for each new entity. These generated values are unique at the database level

Jakarta Persistence (JPA) supports automatic value generation. This feature is primarily useful ... control automatic value generation. Generation configuration Configure field-level generation behavior using the following annotation and enumeration: Specifies that the property or field value

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.CriteriaBuilder.In In value (    T value ) Add to list of values to be tested against. Parameters: value - value Returns: in predicate. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.CriteriaBuilder.In In value (    Expression value ) Add to list of values to be tested against. Parameters: value - expression Returns: in predicate. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.CriteriaBuilder.Coalesce Coalesce value (    T value ) Add an argument to the coalesce expression. Parameters: value - value Returns: coalesce expression. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.DiscriminatorValue String value (Optional) The value that indicates that the row is an entity of the annotated entity type ... is used to generate a value representing the entity type. If the DiscriminatorType is STRING

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.MapJoin Path value () Create a path expression that corresponds to the map value . This method is for stylistic use only: it just returns this. Returns: path corresponding to the map value . Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.CriteriaBuilder.Coalesce Coalesce value (    Expression value ) Add an argument to the coalesce expression. Parameters: value - expression Returns: coalesce expression. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.PersistenceProperty String value The value of the property Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.CriteriaBuilder Expression values (    M map ) Create an expression that returns the values of a map. Parameters: map - map Returns: collection expression. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.QueryHint String value Value of the hint. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.AttributeOverrides AttributeOverride[] value (Required) One or more field or property mapping overrides. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.PersistenceContexts PersistenceContext[] value (Required) One or more PersistenceContext annotations. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.metamodel.StaticMetamodel Class value Class being modelled by the annotated class. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.Temporal TemporalType value The type used in mapping Date or Calendar . Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.TableGenerators TableGenerator[] value Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.IdClass Class value The primary key class, which must declare fields or properties with names and types that match the Id fields and properties of the annotated entity class. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.Enumerated EnumType value (Optional) The type used in mapping an enum type. Default: ORDINAL Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.ForeignKey ConstraintMode value (Optional) Used to specify whether a foreign key constraint should be generated when schema generation is in effect. ConstraintMode.CONSTRAINT specifies that the persistence provider must generate a foreign key

Jakarta Persistence (JPA) Method in jakarta.persistence.OrderBy String value An orderby_list . Specified as follows: orderby_list::= orderby_item [,orderby_item]* orderby_item::= [property_or_field_name] [ASC | DESC] If ASC or DESC is not specified, ASC (ascending order) is assumed

Jakarta Persistence (JPA) Method in jakarta.persistence.NamedEntityGraphs NamedEntityGraph[] value Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.NamedNativeQueries NamedNativeQuery[] value (Required) Array of NamedNativeQuery annotations. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.NamedStoredProcedureQueries NamedStoredProcedureQuery[] value (Required) Array of NamedStoredProcedureQuery annotations. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.NamedQueries NamedQuery[] value (Required) An array of NamedQuery annotations. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.MapKeyClass Class value (Required) The type of the map key. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.MapKeyEnumerated EnumType value (Optional) The type used in mapping a map key enum type. Default: EnumType.ORDINAL Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.MapKeyTemporal TemporalType value (Required) The type used in mapping java.util.Date or java.util.Calendar . Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.MapsId String value (Optional) The name of the attribute within the composite key to which the relationship attribute corresponds. If not explicitly specified, the relationship maps the primary key of the entity. Default: "" Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.NamedAttributeNode String value (Required) The name of the attribute that must be included in the graph. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.MapKeyJoinColumns MapKeyJoinColumn[] value (Required) The map key join columns that are used to map to the entity that is the map key. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.JoinColumns JoinColumn[] value The join columns that map the relationship. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.SecondaryTables SecondaryTable[] value (Required) The secondary tables for an entity. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.Converts Convert[] value The Convert mappings that are to be applied. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.SequenceGenerators SequenceGenerator[] value Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.SqlResultSetMappings SqlResultSetMapping[] value One or more SqlResultSetMapping annotations. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.EntityListeners Class [] value The callback listener classes Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.Cacheable boolean value (Optional) Whether or not the entity should be cached. Default: true Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.PersistenceUnits PersistenceUnit[] value (Required) One or more PersistenceUnit annotations. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.PrimaryKeyJoinColumns PrimaryKeyJoinColumn[] value One or more PrimaryKeyJoinColumn annotations. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.Access AccessType value (Required) Specification of field- or property-based access. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.AssociationOverrides AssociationOverride[] value (Required) The association override mappings that are to be applied to the relationship field or property. Since: Jakarta Persistence (JPA) 1.0

, these operator sets also handle NULL values differently. Comparing NULL values The following table shows how each comparison operator handles NULL values . One column shows the result of comparing a NULL value with a non- NULL value . The other column shows the result of comparing two NULL values : Operator

, where each group has a unique combination of values . Aggregate calculations ( COUNT , SUM , AVG , MAX , MIN ... the five aggregate functions of SQL: COUNT : Returns a long value that represents the number of elements. SUM : Returns the sum of numeric values . AVG : Returns the average of numeric values as

, and automatic sequential value generation . This powerful feature is absent from many other object-oriented ... and can be retrieved by the combination of its type and its primary key. Primary key values must be unique for each entity class. Instances of different entity classes, however, may share the same primary key value

that don't participate in persistence, so their values are never stored in the database ... a value of one of the supported persistable types . ObjectDB supports persistent fields with any declared type, including a generic java.lang.Object , as long as the actual runtime value

`, `Date`, and math types. Multi- value types: Collections, maps, and arrays. Miscellaneous types: Enum ... that function as value types. As with other non-entity types, instances of an embeddable class ... part is discarded when the entity is stored in the database. Multi- value types The following multi

Numeric values can appear in JPQL queries in several forms: As numeric literals , such as 123 ... that return a numeric value , such as INDEX and SIZE . As string functions that return a numeric value , such as ... simple numeric values into more complex expressions. Arithmetic operators JPA supports

, which prevents duplicate values in the indexed field. If you try to commit or flush a transaction where different entities have the same value in a unique field, ObjectDB throws a PersistenceException ... or a unique index if you specify unique="true" . The default value for unique is false

with different parameter values to retrieve different results. Executing the same query multiple times with different parameter values is more efficient than using a new query string for each execution ... is a parameter that serves as a placeholder for a value . Before executing the query, you must set

a persistent field, and each cell contains the value of a field for a specific object. This type ... . Editing values and references You can edit simple field values inline in the Tree and Table viewer windows. Double-click the field, press F2, or type the new value . Use the Edit Edit Multi Line String