ObjectDB Database Search

The JPA Criteria API provides type-safe interfaces for defining query result expressions ... exactly what data is returned and how it is sorted within the result set. SELECT clause elements The following interfaces represent the content of a SELECT clause: Represents a single result item

query = em. createQuery ("SELECT c FROM Country c", Country.class); List results = query. getResultList (); Because the results are managed entities they have all the support that JPA provides ... for deletion , and so on. Query results are not limited to entities. You can use almost any valid JPQL

getSingleResult . Result range (setFirstResult, setMaxResults) The setFirstResult and setMaxResults methods let you define a result window, which is a portion of a large query result list. The setFirstResult method specifies the starting point of the result window by defining how many results to skip from

when exactly one result object is expected. Query.getResultList () : Use in any other case ... when exactly one result object is expected. TypedQuery.getResultList () : Use in any other case. In ... Country c", Country.class); List results = query. getResultList (); Both the Query and TypedQuery

The ORDER BY clause specifies the order for the query results . Any JPQL query that does not include an ORDER BY clause returns results in an undefined and non-deterministic order. ORDER BY ... the results by evaluating the result expressions. Finally, the ORDER BY clause sorts the results by

) is not part of any iterated pair and is therefore excluded from the query results . INNER JOIN ... performance problems. For example, consider the following query execution and result iteration: TypedQuery query = em. createQuery ("SELECT c FROM Country c", Country.class); List results = query

can improve performance by reducing file fragmentation that can result from frequent resize operations ... sync= "false" results in much faster database writes, but sync="true" is safer for production ... for the two query cache mechanisms that ObjectDB manages: The results attribute specifies the size

procedure query, followed by getUpdateCount . The results of executeUpdate will be those of getUpdateCount . The execute method supports both the simple case where scalar results are passed back only via INOUT and OUT parameters as well as the most general case (multiple result sets and/or update

dialect. Groups multiple @NamedNativeQuery definitions on a single class. Result set mapping Map the results of native SQL queries to entities or scalar values using these annotations: Defines how the result set of a native query maps to entities, scalar values, or constructor results . Groups

result type is unknown or when a query returns polymorphic results whose lowest common denominator is Object . When a more specific result type is expected, use the TypedQuery interface. The TypedQuery interface makes it easier to run queries and process results in a type-safe manner. Building queries

The GROUP BY clause groups query results . A JPQL query with a GROUP BY clause returns properties of the resulting groups instead of individual objects and fields. In the query execution order ... . When a query includes a GROUP BY clause, the database objects (or tuples) that result from the FROM clause

is NULL and the other is FALSE , the result is FALSE because one FALSE operand is sufficient to make the expression false. If one operand is NULL and the other is TRUE or NULL , the result is NULL ... and the other is TRUE , the result is TRUE because one TRUE operand is sufficient to make the expression true

of elements. Use the First and Max fields to set the result range. Select the Disable Cache checkbox to bypass the query program and result caches. Click the Execute button to run the query. If the query is valid, the results open in a default viewer ( Tree window by default). The query window then displays

literals dynamically into the query string, which results in more efficient queries. @NamedQuery ... takes a query name and a result type and returns a TypedQuery instance: TypedQuery query = em. createNamedQuery ("Country.findAll", Country.class); List results = query. getResultList

- much faster than any other JPA solution. General Highly optimized code (as a result of many profiling sessions). Unique data structures and algorithms (as a result of years of R&D). Outperforms competing ... (for repeating queries with different arguments). Query result cache (for repeating queries

variable. Finally, the range variable, c , is used in the SELECT clause as the query's result ... , which you can then execute: TypedQuery query = em. createQuery (q); List results = query. getResultList ... ); List results = query. getResultList (); Because both types of queries are ultimately represented by

variables for iterating over data in the database that may be relevant to the query results . Query ... ;with query results .  The following interfaces manage fetch operations within the Criteria API ... over the attribute values. Unlike a standard join, these values cannot be used in the query results or in

The MapJoin interface is the type of the result of joining to a collection over an association or element ... : may result in a runtime failure. Inherited from Expression Parameters: type - intended type ... expression object. Unlike Expression.as , this method does result in a runtime type conversion

of the result of joining to a collection over an association or element collection ... cause type conversion: the runtime type is not changed. Warning: may result in a runtime failure ... Expression.as , this method does result in a runtime type conversion. Providers are required to support

interface is the type of the result of joining to a collection over an association or element collection ... : may result in a runtime failure. Inherited from Expression Parameters: type - intended type ... expression object. Unlike Expression.as , this method does result in a runtime type conversion

of the result of joining to a collection over an association or element collection ... not cause type conversion: the runtime type is not changed. Warning: may result in a runtime failure ... Expression.as , this method does result in a runtime type conversion. Providers are required

does not cause type conversion: the runtime type is not changed. Warning: may result in a runtime ... Expression.as , this method does result in a runtime type conversion. Providers are required ... FetchParent Parameters: attribute - target of the join Returns: the resulting fetch join. Since: Jakarta

: - the type of the defined result Super Interfaces: AbstractQuery , CriteriaSelect ... query results are eliminated. A true value will cause duplicates to be eliminated. A false value will cause duplicates to be retained. If distinct has not been specified, duplicate results

. Warning: may result in a runtime failure. Inherited from Expression Parameters: type - intended type ... , returning a new expression object. Unlike Expression.as , this method does result in a runtime type ... : the resulting fetch join. Since: Jakarta Persistence (JPA) 1.0 Fetch fetch ( SingularAttribute attribute

numeric promotion principles. For example, the result of a binary arithmetic operation on an int value ... of a numeric argument. The result is always a positive number or zero. For example: ABS(-5) evaluates to 5 ... arguments and returns an integer value. If both operands have the same type, the result

with different parameter values to retrieve different results . Executing the same query multiple times ... filters the query results to Country objects whose name field is equal to :name . The :name identifier ... has several drawbacks. First, the query is not reusable. Different literal values result in different query

identification variables and SELECT result variables. Parameters : Instances of these classes that are assigned ... to the associated Capital entity. A path expression whose result is a user-defined persistent class ... only if its result is also a user-defined persistent class. The dot ( . ) operator cannot be applied

locking wait times. Query exceptions Exceptions specific to query execution and result retrieval: Thrown by Query.getSingleResult() when the query returns no results . Thrown by Query.getSingleResult() when the query returns more than one result . Thrown when a query exceeds the specified timeout limit

. Warning: may result in a runtime failure. Inherited from Expression Parameters: type - intended type ... , returning a new expression object. Unlike Expression.as , this method does result in a runtime type ... : the resulting fetch join. Since: Jakarta Persistence (JPA) 1.0 Fetch fetch ( SingularAttribute

conversion: the runtime type is not changed. Warning: may result in a runtime failure. Inherited from ... , this method does result in a runtime type conversion. Providers are required to support casting ... : attribute - target of the join Returns: the resulting fetch join. Since: Jakarta Persistence (JPA

an all expression over the subquery results . Parameters: subquery - subquery Returns: all expression ... any ( Subquery subquery ) Create an any expression over the subquery results . This expression ... to specify a constructor that is applied to the results of the query execution. If the constructor

must also be flushed before execution of any query whose result set would be affected by unflushed modifications ... ( ConnectionFunction function ) Call the given function and return its result using the database connection ... result Returns: the new query instance. Throws: IllegalArgumentException - if a query has not

. Warning: may result in a runtime failure. Inherited from Expression Parameters: type - intended type ... a new expression object. Unlike Expression.as , this method does result in a runtime type ... distinct ) Specify whether duplicate query results are eliminated. A true value will cause duplicates

interfaces is structured as follows: Selection # Base interface for result items └─ Expression # Base ... ;to allow using expression as query results . A boolean expression used to define restrictions in

resulting from mechanical transformation or translation of a Source form, including but not limited ... , incidental, or consequential damages of any character arising as a result of this License or

this case, the employees field is populated with the results of the following query: SELECT e FROM ... results by specifying the key field with the @MapKey annotation: @Entity public class Department

and recording files and attempts to apply all the recorded operations. The resulting database file ... and applies all operations up to transaction 1000, the resulting file is named 1000.odb .

instances of the following interface: Represents a named query, including its name, result type, and hints. Retrieve it by result type from EntityManagerFactory.getNamedQueries , and use it to get a TypedQuery instance via EntityManager.createQuery .

for queries where the result type is known. It is preferred over the legacy Query interface because it eliminates the need for casting results . Controls the execution of stored procedures (not applicable

to the SELECT clause to be collected as query results , the WHERE clause acts as a filter. The boolean ... and collected as query results . WHERE predicate and indexes Formally, the WHERE clause functions as a filter

and eliminates the ORM layer. The result is better performance and faster applications, especially when the object data model is complex. See JPA benchmark results ...   Reduce development time. Improve

, and if a court requires any other Contributor to pay any damages as a result , the Commercial ... arose. Each party waives its rights to a jury trial in any resulting litigation.

a result of either a global or local setting) during a persist operation. The on-commit attribute specifies whether to apply cascading (as a result of either a global or local setting) during commit

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

Jakarta Persistence (JPA) Interface jakarta.persistence.TypedQuery Type Parameters: - query result ... result the query object was set to retrieve. Returns 0 if setFirstResult was not applied to the query object. Inherited from Query Returns: position of the first result . Since: Jakarta Persistence (JPA

. Since: Jakarta Persistence (JPA) 3.2 int getFirstResult () The position of the first result the query object ... : position of the first result . Since: Jakarta Persistence (JPA) 2.0 The Running JPA Queries article ... int getMaxResults () The maximum number of results the query object was set to retrieve. Returns

: - the type of the result Super Interfaces: CommonAbstractCriteria The AbstractQuery interface defines ... results are eliminated. A true value will cause duplicates to be eliminated. A false value will cause duplicates to be retained. If distinct has not been specified, duplicate results must be retained

not cause type conversion: the runtime type is not changed. Warning: may result in a runtime failure ... Expression.as , this method does result in a runtime type conversion. Providers are required ... Expression otherwise ( R result ) Add an "else" clause to the case expression. Parameters: result

of the result of the native SQL query. Query names are scoped to the persistence unit. A named query ... how the native SQL query result set should be interpreted, for example: @NamedNativeQuery( name ... ) AND (i.name = 'widget')", resultClass = com.acme.Order.class ) In more complicated cases, a result

( 20 ): You may click Preview Results  to see the query results : Close the dialog box by clicking