ObjectDB Database Search

Please read carefully this software license agreement. By downloading, installing or using ... of this agreement will be binding, unless in writing and signed by an authorized representative of each party. 1 ... other humanly perceivable form. The Customer will use its best efforts and take all reasonable steps

As explained in Chapter 2 , you can delete entities from the database by following these steps ... within an active transaction, either explicitly by calling the remove method or implicitly through a cascading operation. Apply changes to the database by calling the commit method. JPQL DELETE queries provide

In JPA, a database connection is represented by the EntityManager interface ... an EntityManager instance is a two- step process. First, you obtain an EntityManagerFactory instance ... directory, which by default is the directory where ObjectDB is installed. If a database file does not

What are the steps of creating small web app?

. Use its static methods to create an EntityManagerFactory as the first step for accessing

and a.startDate ?1)) the composite index is not used, query plan:  Step 1: Process Action (a) instances ------------------------------------ [ Step 1a] Scan index com.agile.hummingbird.Action[startDate] locating all the Action (a) instances. [ Step 1b] Filter the results of step 1a retaining

WHERE v. step .stepNumber = ? is very slow in comparing to the query: SELECT v FROM Values v WHERE v ... = CascadeType.REMOVE) private Values valuesRef; }   @Index (members = {" step .stepNumber"}) @Entity ... ; @OneToOne (fetch = FetchType.EAGER) private TCStep step ; //For performance reasons, we use a list

and sometimes we don't get the entity by query. Have you an idea what happens here?   btc_es BTC EmbeddedSystems

============================ [ Step 1] Scan index com.agile.hummingbird.Action[endDate] locating all the Action (a) instances. [ Step 2] Retrieve fields in Action (a) instances. [ Step 3] Filter the results of step 2 retaining only results that satisfy: (a.transferred=0). [ Step 4] Filter the results of step

where receiver == :r order by id desc Query Plan Description ====================== [ Step 1] Scan index com ... : (this.receiver==:r). [ Step 2] Order the results of step 1 by : desc(any(any(this.id))). [ Step 3] Apply ... NmeaBatch where receiver == :r order by id desc Query Plan Description ====================== [ Step 1

of the entity attribute Interface implemented by custom attribute converters . A converter is a class ... as the type of a persistent field or property, and a basic type used as an intermediate step in ... column for use by the JDBC driver: i.e., persistence providers are not expected to do such type

application manages a basic guestbook page. Every visitor can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest entity and all the Guest

manages a basic guestbook page. Every visitor can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest JPA entity and all the Guest entities

can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest entity and all the Guest entities are stored in an ObjectDB database. Required Software

. The demo web application manages a basic guestbook page. Every visitor can sign the guestbook by ... is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest entity ... would be the same). The Tutorial Steps This tutorial consists of the following steps :

. Every visitor can sign the guestbook by filling a simple form. The visitors that have already signed are listed below the form: Persistence is managed by JPA. Every visitor that has signed the guestbook is represented by a Guest entity and all the Guest entities are stored in an ObjectDB database

3 web application: Spring MVC and JPA Maven Projects for Download The tutorials provide  step by step instructions on how to create the sample applications. In addition, the sample applications

--------------------- Group the results of step 5 by : a.endDate,v$1.nodePath,v$3.doubleValue. Step 7: Apply ... .properties.name = 'scheduledSlot') GROUP BY a.endDate, a.objectsInCharge.nodePath, a.objectsInCharge ... we can see that this index is not used: Query Plan Description ====================== Step 1: Process

Description ====================== Step 1: Process IndividualContact ($1) instances ------------------------------------------------ [ Step 1a] Scan type com.quasado.foundation.communication.api.model.contact.individual.IndividualContact locating all the IndividualContact ($1) instances. [ Step 1b

.classIdentifier='(TC)')). [ Step 1b] Order the results of step 1a by :   v$1. [ Step 1c] Scan index com.agile ... )')). [ Step 1d] Order the results of step 1c by :   v$1. [ Step 1e] Merge the results of steps 1b ... results --------------------- Group the results of step 4 by :   o. [ Step 6] Remove duplicates

the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document. "Licensor" shall mean the copyright owner or entity authorized by the copyright ... and all other entities that control, are controlled by , or are under common control with that entity

and final entity fields are always considered transient. You can declare other fields as transient by using ... -final entity field is persistent by default unless specified otherwise (for example, by using ... its methods or code. This state is reflected by its persistent fields, including fields inherited from

are represented in queries by entity names . By default, the entity name is the unqualified name ... can be set explicitly by using the name attribute of the @Entity annotation: @Entity ( name ="MyName ... is declared as embeddable by marking it with the @Embeddable annotation: @Embeddable public class Address

the no-argument constructors of entity classes and keep them as simple as possible. Retrieval by class and primary key Every entity can be uniquely identified and retrieved by the combination of its class ... is similar to the find method, but if the entity is not already managed by the EntityManager

additions to the Program originate from and are distributed by that particular Contributor. A Contribution 'originates' from a Contributor if it was added to the Program by such Contributor itself or ... entity that distributes the Program. "Licensed Patents" mean patent claims licensable by

well (dialog boxes and menus might look slightly different but the code would be the same). This tutorial consists of the following steps :

for each new database file. The resize attribute specifies the size by which to extend the database ... can improve performance by reducing file fragmentation that can result from frequent resize operations ... environments. By default, the recovery file is created in the same directory as the database file

By default, the name of an entity class in a JPQL query is the unqualified name of the class (for example, Country with no package name). The default name can be overridden by specifying another name ... to a single-value expression are less commonly used because they can usually be replaced by

The ObjectDB Enhancer is a post-compilation tool that improves performance by modifying ... directly accessing persistent fields of other classes. This practice is required by the JPA specification but not enforced by ObjectDB. Instead, use the accessor and mutator methods of the desired class

a Country object from the database by its name: public Country getCountryByName( EntityManager em ... a value for the parameter by using the setParameter method. The setParameter method supports method chaining by returning the TypedQuery instance on which it was invoked. This allows you to chain

Using Jakarta Persistence (JPA) You can store new entities in the database either explicitly by ... . The exception is thrown either by persist , if the existing entity is currently managed by the EntityManager , or by commit . Referenced embedded objects The following code stores an Employee instance

Detached entities are objects in a special state where they are not managed by an EntityManager ... have limited functionality: Many JPA methods, for example, lock , do not accept detached objects. Retrieval by ... EntityManager instances. Explicit detach You can detach an entity by using the detach method: em

A connection to a database is represented by an EntityManager instance, which also provides methods ... connection by using a separate EntityManager instance for each HTTP request. The main role ... transactions. Transactions are managed by an EntityTransaction instance, which is obtained from

query returns Country objects, which then become managed by the EntityManager instance em : TypedQuery ... directly. However, you can add their content to the SELECT clause by using a bound JOIN variable in ... with the containing entities. Therefore, embedded objects that are retrieved directly by a result path expression

method specifies the starting point of the result window by defining how many results to skip from ... because the setter methods in Query and TypedQuery support method chaining by returning the query object on which they were invoked. Flush mode (setFlushMode) Changes made to a database by using an EntityManager

; CriteriaQuery , CriteriaUpdate , and  CriteriaDelete are first built by static methods ... to define SELECT, WHERE , GROUP BY , and ORDER BY clauses. To execute the query, pass the instance ... (Note: Subqueries are currently not supported by ObjectDB). Top-level queries and subqueries share

of step 4 by : d. [ Step 6] Remove duplicates from the groups of step 5. [ Step 7] Apply selection ... = '1344770') Query plan 1/2 description ============================ [ Step 1] Scan type eu.extech ... that satisfy: (d.productVariantOid='1344770'). [ Step 2] Scan type eu.extech.quant.product_variants.data

files). Recording is disabled by default and can be enabled in the configuration . The ObjectDB Replayer ... . This feature is useful for two purposes: Recovering from a database failure by replaying the recorded operations. Reproducing problems during debugging by repeating a failure. Recording transactions

of up to six clauses in the following format: SELECT ... FROM ... [WHERE ...] [GROUP BY ... [HAVING ...]] [ORDER BY ...] The SELECT and FROM clauses are required in every query that retrieves data; update and delete queries have a slightly different structure. The other JPQL clauses-- WHERE , GROUP BY

) numeric literals. This feature is not supported by all JPA implementations. String literals JPQL ... , 'Adam' or '' ), and a single quotation mark within a string is represented by two single quotation ... escape characters (for example, "Adam\'s" and "abcd 1234" ). However, this syntax is not supported by

, while Java uses its own notation, which is also used by the JDO Query Language (JDOQL). ObjectDB ... , Boolean expressions are represented by the Expression interface and its descendants. For example, a Boolean path (a field or property) is represented by Path : Path isInUN = country. get ("isInUN

As demonstrated in this forum thread , a mapped by collection field with lazy fetch mode is not initialized in results of a query that uses JOIN FETCH on that collection field (when enhancement is used). support Support   Build 2.4.1_06 fixes this issue (fields are now initialized

: (u.userName=:userName). [ Step 2] Order the results of step 1 by : u. [ Step 3] Use NULL as a result ... for :userName parameter 2.8.9 Query plan description ============================ [ Step 1] Scan type User locating all the User (u) instances. [ Step 2] Evaluate fields in User (u) instances. [ Step 3

. Creating and traversing. For the traversing we access the data block by block - in each block step by step and in each step value by value. When do this within one transaction without holding ... s : sb. steps ) { MyValue v : s.values. get ( 0 ); } } The values are not referenced by

via a call to close , to allow resources to be cleaned up by the persistence provider. This approach places ... EntityManager may be obtained by dependency injection, using PersistenceContext . // inject the container ... the EntityTransaction obtained by calling getTransaction . A complete idiom for custom application

master databases, slave databases ( by using one or more elements), and databases that are not ... by a server on localhost:6000 and a slave database managed by a server on localhost:6001 . In ... ;user=b;password=b" ); A composite URL contains two or more database URLs separated by a pipe character

named queries instead of dynamic queries can improve code organization by separating JPQL query ... , you should choose names carefully to avoid collisions, for example, by using the unique entity name as ... Queries at Runtime At runtime, named queries are represented by the Query and TypedQuery interfaces

====================== Step 1: Process Mitglied ($1) instances --------------------------------------- [ Step 1a] Scan ... ) instances. [ Step 1b] Evaluate fields in Mitglied ($1) instances. Step 2: Process IndividualProfile ($3) instances   (for every result of step 1

An ObjectDB server can manage one or more databases. Databases that are managed by a server can be accessed by multiple processes simultaneously. In addition, the server supports accessing these databases from remote computers by TCP/IP. More details about client server mode vs. embedded database

store methods and code. Only the state of the object as reflected by its persistent fields is stored. Persistent fields, by default, are all the fields that are not defined as static , final or ... types above are defined as optional by JDO (arrays and most of the collection classes), but ObjectDB