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identified in a query string by their special form, which is a colon (:) followed by a valid JPQL ... appearing in the query string. The parameter type is inferred by the context. In the above example ... . Queries can include multiple parameters, and each parameter can occur multiple times in the query

Literals in JPQL, as in Java, represent constant values. JPQL supports various types of literals ... parameter values. Literals should only be embedded in JPQL queries when a single constant value ... to null in Java and SQL. Since JPQL is case insensitive, NULL , null and Null are equivalent. Notice

in ObjectDB (and in JPA) is always at the database object level, i.e. each database object ... to pessimistic locking it is easier to use and more efficient. In the rare cases in which update collision ... object. The initial version of a new entity object (when it is stored in the database for the first

Collections may appear in JPQL queries: as parameters - when collections are assigned as arguments. as  path expressions - in navigation to persistent collection fields. IS [NOT] EMPTY ... of elements in a specified collection. For example: SIZE(c.languages)  is evaluated

classes) are represented in JPQL by the following types of expressions: Variables - FROM ... defined persistable classes can participate in direct comparison using the = and operators. But more often they are used in JPQL path expressions that navigate to values of simple types (number, boolean

String values may appear in JPQL queries in various forms: as  string literals - e.g. 'abc' , ''. as parameters - when string values are assigned as arguments. as  path expressions - in ... ;is evaluated to TRUE . '100' LIKE '%\%' ESCAPE '\' is evaluated to FALSE . In the expressions

Most JPQL queries use at least one comparison operator in their WHERE clause. Comparison Operators ObjectDB supports two sets of comparison operators, as shown in the following table:   Set 1 ... != The two sets differ in the Equal and the Not Equal operators. JPQL follows the SQL notation, where Java uses

Logical operators in JPQL and in JPA criteria queries enable composition of complex JPQL boolean ... of logical operators, as shown in the following table: Set 1 - JPQL / SQL Set 2 - Java / JDO AND && OR || NOT ! JPQL follows the SQL notation, while Java uses its own notation (which is also in use by JDOQL

Numeric values may appear in JPQL queries in many forms: as  numeric literals - e.g. 123 , -12.5 . as parameters - when numeric values are assigned as arguments. as  path expressions - in ... also supports the % (modulo) and the ~ (bitwise complement) operators that are supported in Java

Existing entity objects can be updated, as explained  in chapter 2 , by: Retrieving ... , but when executed, update the content of specified entity objects in the database. Updating entity objects in ... that a cached entity object in its persistence context has been modified by an UPDATE query

Date and time expressions may appear in JPQL queries: as date and time literals - e.g. {d '2011-12 ...   path expressions - in navigation to persistent date and time fields. as results of predefined ... to 0 . Date and Time in Criteria Queries The CriteriaBuilder interface provides three factory methods

As explained  in chapter 2 , entity objects can be deleted from the database by ... that a cached entity object in its persistence context has been removed from the database by ... the java.lang.Object  class in queries (as an extension to JPA), so the following query

JPA Interface In Super Interfaces: Expression , Predicate , Selection , TupleElement Interface used to build in predicates. Since: JPA 2.0 Public Methods Expression getExpression () Return ... .0 CriteriaBuilder. In value ( Expression  value) Add to list of values to be tested

JPA Method in javax.persistence.criteria.CriteriaBuilder CriteriaBuilder. In in (    Expression  expression ) Create predicate to test whether given expression is contained in a list of values. Parameters: expression - to be tested against list of values Return: in predicate Since: JPA 2.0

JPA Method in javax.persistence.criteria.CriteriaBuilder$ In CriteriaBuilder. In value (    Expression  value ) Add to list of values to be tested against. Parameters: value - expression Return: in predicate Since: JPA 2.0

JPA Method in javax.persistence.criteria.CriteriaBuilder$ In CriteriaBuilder. In value (   T value ) Add to list of values to be tested against. Parameters: value - value Return: in predicate Since: JPA 2.0

JPA Method in javax.persistence.criteria.CriteriaBuilder$ In Expression getExpression () Return the expression to be tested against the list of values. Return: expression Since: JPA 2.0

JPA Enum Constant in javax.persistence.ParameterMode IN Stored procedure input parameter Since: JPA 2.1

JPA Method in javax.persistence.criteria.Expression Predicate in (   Collection  values ) Create a predicate to test whether the expression is a member of the collection. Parameters: values - collection of values to be tested against Return: predicate testing for membership Since: JPA 2.0

JPA Method in javax.persistence.criteria.Expression Predicate in (    Expression  values ) Create a predicate to test whether the expression is a member of the collection. Parameters: values - expression corresponding to collection to be tested against Return: predicate testing for membership Since: JPA 2.0

JPA Method in javax.persistence.criteria.Expression Predicate in (    Expression ... values ) Create a predicate to test whether the expression is a member of the argument list. Parameters: values - expressions to be tested against Return: predicate testing for membership Since: JPA 2.0

JPA Method in javax.persistence.criteria.Expression Predicate in (   Object... values ) Create a predicate to test whether the expression is a member of the argument list. Parameters: values - values to be tested against Return: predicate testing for membership Since: JPA 2.0

to view data in ObjectDB databases, execute JPQL and JDOQL queries and edit the content of databases. Running the Explorer The ObjectDB Explorer is contained in the explorer.jar executable jar file, which is located in the bin directory of ObjectDB. It depends on the objectdb.jar file. You can run

, persistent and inverse fields) can be used in both entity classes and embeddable classes . However, the last two groups (primary key and version fields) can only be used in entity classes. Primary key fields are discussed in the Primary Key section. Transient Fields Transient entity fields are fields

OF THIS AGREEMENT. 1. DEFINITIONS "Contribution" means: a) in the case of the initial Contributor, the initial code and documentation distributed under this Agreement, and b) in the case of each subsequent ... which: (i) are separate modules of software distributed in conjunction with the Program

The term persistable types refers to data types that can be used for storing data in the database ... can be stored in the database directly. Other persistable types can be embedded in entity classes as fields . In addition, only instances of entity classes preserve identity and are stored

clause in the query execution order is after the FROM and WHERE clauses, but before the SELECT clause. When a GROUP BY clause exists in a JPQL query, database objects (or tuples of database objects ... over all the Country objects in the database. The GROUP BY clause groups these Country objects by

New entity objects can be stored in the database either explicitly by invoking the persist method ... an instance of the Employee entity class in the database: Employee employee = new Employee("Samuel ... its state to Managed. The new entity object is stored in the database when the transaction

The FROM clause declares query identification variables that represent iteration over objects in the database. A query identification variable is similar to a variable of a Java enhanced for loop in ... at the WHERE clause level by using a type expression . For example, in the following query, c iterates

Querying without indexes requires iteration over entity objects in the database one by ... . Index management introduces overhead in terms of maintenance time and storage space, so deciding ... that prevents duplicate values in the indexed field. A PersistenceException is thrown on commit (or flush

entity object is not found in the persistence context a new object is constructed and filled ... . Therefore, it is recommended to avoid unnecessary time consuming operations in no-arg constructors ... object in its persistence context no retrieval is required and the existing managed object

the Service. By using the Service, You agree to the collection and use of information in accordance ... shall have the same meaning regardless of whether they appear in singular or in plural. Definitions ... ", "We", "Us" or "Our" in this Agreement) refers to ObjectDB Software Ltd, 109 Vernon House Friar Lane Unit 632

mean the work of authorship, whether in Source or Object form, made available under the License, as indicated by a copyright notice that is included in or attached to the work (an example is provided in the Appendix below). "Derivative Works" shall mean any work, whether in Source or Object form

is packaged in the main ObjectDB development jar file (odbfe.jar / odbee.jar / odbse.jar), located in ... the Explorer on Windows using the explorer.exe application, located in the bin directory. Notice ... is equivalent to the following command: java -Xms16m -Xmx512m -jar odbfe.jar In addition, any JVM argument

Objects Persistent In JDO applications, every object in memory is either a persistent object, i.e ... is automatically stored in the database when the transaction is committed (unless it is being deleted before commit ... is also thrown if the argument to makePersistent( ... ) is not an instance of a persistent class (as defined in

JDO Method in javax.jdo.identity.IntIdentity void readExternal (   ObjectInput  in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

JDO Method in javax.jdo.identity.CharIdentity void readExternal (   ObjectInput  in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

JDO Method in javax.jdo.identity.ObjectIdentity void readExternal (   ObjectInput  in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

JDO Method in javax.jdo.identity.LongIdentity void readExternal (   ObjectInput  in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

JDO Method in javax.jdo.identity.ByteIdentity void readExternal (   ObjectInput  in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

JDO Method in javax.jdo.identity.ShortIdentity void readExternal (   ObjectInput  in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

JDO Method in javax.jdo.identity.StringIdentity void readExternal (   ObjectInput  in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

JDO Method in javax.jdo.identity.SingleFieldIdentity void readExternal (   ObjectInput  in ) Read from the input stream. Creates a new instance with the target class name set Since: JDO 1.0

There are various ways to retrieve objects from an ObjectDB database, as shown in section 6.3 ... to boost recycling rates in Manchester approved n criteria, and iteration over the results in ... (usually a persistent class) A filter, which is a boolean expression in a Java like syntax The query

more persistent classes. All the persistent classes, and only them, have to be declared in a metadata ... and the other resources (possibly in a jar file). 4.1  JDO Metadata Files During JDO enhancement and later ... description of each class in several .jdo files in a pre defined order. If a metadata description

, step by step. Both sample programs are contained in ObjectDB's samples directory. 2.1  Hello World The HelloWorld sample program manages a list of strings in the database. Each time the program is run another string is stored in the database and all the strings in the database are printed

can be accessed by multiple processes simultaneously. In addition, the server supports accessing ... mode are discussed in Section 1.2 . Because the JDO API and the format of the database file are the same in both modes, switching between these two modes can be done very easily by simply changing

storing, retrieving, updating and deleting database objects, are provided in the next chapter ... database connections during their lifetime. For instance, in a web application it is very common to establish a separate database connection for every web request. In general, holding a database connection

Persistent Classes are user defined classes whose instances can be stored in a database using JDO. Instances of these classes that represent objects in the database are called persistent objects or persistent instances . Objects that do not represent anything in the database (including instances

ObjectDB for Java/JDO is a powerful Object Database Management System (ODBMS) written entirely in ... with tables, records and SQL in addition to the application's classes and objects. ObjectDB is JDO ... DB2 and Microsoft SQL Server. In addition, by using JDO you are backed up by a large community