 30 | Method javax.persistence.criteria.Subquery Subquery groupBy( List grouping ) Specify the expressions that are used to form groups over the subquery results. Replaces the previous specified grouping expressions, if any. If no grouping expressions are specified, any previously added |
30 | attributes, grouping queries and aggregate queries) which are usually missing from Object Oriented ... query FETCH JOIN. Configurable JDO fetch groups. Ease of Use and Learning ObjectDB is very simple ... . Persistence is set using JPA/JDO annotations (e.g. @Entity, @Id, @Index). Transparent activation |
30 | attributes, grouping queries and aggregate queries) which are usually missing from Object Oriented ... query FETCH JOIN. Configurable JDO fetch groups. Ease of Use and Learning ObjectDB is very simple ... . Persistence is set using JPA/JDO annotations (e.g. @Entity, @Id, @Index). Transparent activation |
30 | attributes, grouping queries and aggregate queries) which are usually missing from Object Oriented ... . Configurable JDO fetch groups. Ease of Use and Learning ObjectDB is very simple to use and is easier ... /JDO annotations (e.g. @Entity, @Id, @Index). Transparent activation (no activation depth) - objects |
29 | Method javax.jdo.Query void setGrouping( String group ) Set the grouping expressions, optionally including a "having" clause. When grouping is specified, each result expression must either be an expression contained in the grouping, or an aggregate evaluated once per group. Parameters: group |
28 | Method javax.jdo.PersistenceManagerFactory void addFetchGroups( FetchGroup... groups ) Add the FetchGroups to the set of active fetch groups. FetchGroups are made unmodifiable before being added ... : groups - an array of FetchGroups Throws: SecurityException - if the caller is not authorized for JDOPermission ("manageMetadata") Since: JDO 2.2 |
28 | Method javax.jdo.PersistenceManagerFactory void removeFetchGroups( FetchGroup... groups ) Remove the FetchGroups from the set of active FetchGroups. Existing FetchGroups that match parameter ... . Parameters: groups - an array of FetchGroups Throws: SecurityException - if the caller is not |
28 | superclasses) can be classified into the following five groups: Transient fields Persistent fields Inverse (Mapped By) fields Primary key (ID) fields Version field The first three groups (transient, persistent ... two groups (primary key and version fields) can only be used in entity classes. Primary key fields |
27 | . To minimize round trips to the database server, IDs are allocated in groups. The number of IDs in each ... number generator for every database. This number generator is used to generate automatic object IDs ... @GeneratedValue with the AUTO strategy:
@Entity
public class EntityWithAutoId1 {
@Id @GeneratedValue |
25 | javax.persistence Annotation Id Target: Fields (including property get methods) Specifies the primary key of an entity. The field or property to which the Id annotation is applied ... :
@Id
public Long getId() { return id; } Since: JPA 1.0 See Also: Column GeneratedValue Learn |