Home » Search

About Group Id

1-10 of 200Refresh
Manual
127

GROUP BY and HAVING clauses

The GROUP BY clause enables grouping of query results. A JPQL query with a GROUP BY clause returns properties of generated groups instead of individual objects and fields. The position of a GROUP BY ... clause. When a GROUP BY clause exists in a JPQL query, database objects (or tuples of database objects
Tutorial
101

Step 1: Create a Maven Web Project

a filter, select maven-archetype-webapp in the artifact list and click Next. Enter Group Id (e.g. Guestbook), Artifact Id (e.g. Guestbook), Version (e.g. 1.0) and Package (guest), and click Finish ... >      <id>objectdbid>    ObjectDB Repository
Tutorial
100

Step 1: Create a Maven Web Project

Name (e.g. Guestbook) and select Java EE 5. Enter Maven Group Id (e.g. com.objectdb.tutorial.spring ... .sourceEncoding>      <id>objectdbid>    ObjectDB ... >        <id>enhanceid>        process-classes                java
JDO Doc
71

JDO Predefined ID Classes

An object ID is a combination of a persistence capable class and a primary key. It provides a unique representation of a persistent object. The following classes serve as predefined ID classes for persistence capable classes with a simple single field primary key: Object IDs are used in many
Result
34

ObjectDB Object Database Features

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
Manual
32

JPA Entity Fields

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
Manual
30

Auto Generated Values

. 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
Manual
26

JPA Primary Key

an object database, ObjectDB supports implicit object IDs, so an explicitly defined primary key is not ... key field: @Entity public class Project { @Id @GeneratedValue long id; // still set automatically : } The @Id annotation marks a field as a primary key field. When a primary key field
JPA Doc
26

groupBy(grouping)

grouping ) Specify the expressions that are used to form groups over the query results. Replaces the previous specified grouping expressions, if any. If no grouping expressions are specified, any previously added grouping expressions are simply removed. Parameters: grouping - list of zero or
JPA Doc
26

groupBy(grouping)

Method javax.persistence.criteria.AbstractQuery AbstractQuery groupBy(   Expression... grouping ) Specify the expressions that are used to form groups over the query results. Replaces the previous specified grouping expressions, if any. If no grouping expressions are specified, any previously