ObjectDB Database Search

Literals in JPQL , as in Java, represent constant values. JPQL supports various types of literals ... type literals (for example, Country ). Use JPQL literals sparingly. Queries that use parameters ... times with different parameter values. Embed literals in JPQL queries only when a single, constant

The syntax of the Jakarta Persistence Query Language ( JPQL ) is similar to SQL. This is a key ... with it. The main difference between SQL and JPQL is that SQL operates on relational database tables, while JPQL operates on Java classes and objects. For example, a JPQL query can retrieve entities, unlike SQL

The ability to retrieve managed entities is a key advantage of JPQL . For example, the following ... for deletion , and so on. Query results are not limited to entities. You can use almost any valid JPQL ... must always be specified explicitly. JPQL does not support the the SELECT * expression, which is common in SQL

By default, the name of an entity class in a JPQL query is the unqualified name of the class ... variables represent iteration over all the database objects of a specified entity type. JPQL provides ... variable: SELECT c1, c2 FROM Country c1 INNER JOIN c1.neighbors c2 In JPQL , JOIN can appear only in

is small, which makes indexes even more essential. JPQL expressions in WHERE The previous queries ... JPQL expression syntax , which includes many operators (arithmetic, relational, and logical) and functions (numeric, string, and collection). The WHERE predicate is always a boolean JPQL expression

The Jakarta Persistence Query Language ( JPQL ) is an object-oriented version of SQL. Users familiar with SQL should find JPQL easy to learn and use. This chapter explains how to use JPQL ... the JPQL syntax in detail: The next two sections cover the Jakarta Persistence Query Language ( JPQL

JPQL and criteria queries are built on query expressions. Every query consists of clauses , such as SELECT , FROM , WHERE , GROUP BY , HAVING , and ORDER BY . Each clause is composed of JPQL or Criteria API expressions. Atomic expressions The atomic query expressions are: JPQL / Criteria Variables

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: JPQL ... . != ) operators. JPQL follows SQL notation, while Java uses its own notation, which is also used by JDOQL

The ORDER BY clause specifies the order for the query results. Any JPQL query that does not ... c FROM Country c WHERE c.population 1000000 ORDER BY c.population When using ObjectDB, any JPQL ... are more restrictive. Path expressions are supported by all JPA implementations, but support for other JPQL

String values can appear in JPQL queries in several forms: As string literals , for example, 'abc ... that navigate to persistent string fields. As the results of predefined JPQL string manipulation functions ... . Criteria query string expressions Query String Expressions The JPQL string operators and functions

Date and time expressions can appear in JPQL queries in the following ways: As date and time ... the results of predefined JPQL functions that return the current date and time. Current date and time JPA defines special JPQL expressions that return the date and time from the database server

Collections can appear in JPQL queries in the following ways: As parameters when a collection ... not contain 'English' , and FALSE otherwise. As an extension to standard JPQL , ObjectDB allows ... are synonyms. Criteria query collection expressions The JPQL collection operators and functions

Logical operators in JPQL and JPA criteria queries combine simple Boolean expressions to form complex expressions. Logical operators ObjectDB supports two sets of logical operators, as shown in the following table: Set 1: JPQL / SQL Set 2: Java / JDO AND && OR || NOT ! JPQL uses SQL notation

classes) are represented in JPQL by the following types of expressions: Variables : FROM ... . However, they are more often used in JPQL path expressions that navigate to values of simple types, such as ... through a null reference. In JPQL , the current FROM variable (or FROM tuple, when there are multiple

Numeric values can appear in JPQL queries in several forms: As numeric literals , such as 123 and -12.5 . As parameters that are bound to numeric arguments. As path expressions that navigate ... type and always returns a double value. Criteria query arithmetic expressions JPQL arithmetic operators

operation. Apply changes to the database by calling the commit method. JPQL DELETE queries provide

You can update existing entities, as explained in chapter 2 , by following these steps: Retrieve the entities into an EntityManager . Update the relevant entity fields within an active transaction. Apply the changes to the database by calling the commit method. JPQL UPDATE queries provide

dynamic queries whose structure is known only at runtime. JPA Criteria API vs. JPQL JPQL queries ... compile-time error checking. Errors in string-based JPQL queries, however, are found at runtime. Many developers find string-based JPQL queries easier to use and understand

The GROUP BY clause groups query results. A JPQL query with a GROUP BY clause returns properties ... the result. Although ObjectDB allows JPQL expressions almost anywhere in a query, the preceding query ... : SELECT DISTINCT SUBSTRING(c.name, 1, 1) FROM Country c GROUP BY with aggregate functions JPQL supports

("SELECT c FROM Country c", Country.class); In the preceding code, the same JPQL query ... because it introduces the Country class to ObjectDB. Dynamic JPQL , Criteria API, and named queries In JPA, building queries by passing JPQL query strings directly to the createQuery method is called

their format: a colon (:) followed by a valid JPQL identifier that serves as the parameter name. JPA ... Parameters (?index) In addition to named parameters, which use the :name format, JPQL also supports ordinal ... the application to JPQL injection attacks. For example, suppose the name parameter is received as user input

the query language to one of the following: " JPQL " (JPA Query Language), "JDOQL" (JDO Query Language), or "ODBQL" (ObjectDB Query Language). The default is ODBQL , which is a union of JPQL , JDOQL, and ObjectDB extensions. Setting the language to " JPQL " is useful for enforcing portable JPA code

Jakarta Persistence provides powerful APIs for executing database queries using JPQL strings or ... EntityManager  methods such as createQuery to build  query objects using: Direct JPQL query strings ... rather than string-based JPQL . Criteria queries are built using CriteriaBuilder : This is the main factory

and Reporting Tools (BIRT). It adds support for ObjectDB as a data source and JPQL as a data set query language ... data source. Data sets and JPQL To create the data set: Open the New Data Set dialog box by right ... ) and click Next . Enter a JPQL or a JDOQL query and click Finish . See the Report Generation with BIRT and JPA tutorial for more detailed instructions.

supports two object-oriented query languages - JPQL and JDOQL . Query Languages JPQL - Java Persistence ... FETCH ). WHERE (with both JPQL and JDOQL expressions). GROUP BY (including HAVING and aggregates

it to view data, execute JPQL and JDOQL queries, and edit database content. Running the Explorer ... window lets you run JPQL and JDOQL queries, as discussed later. Closing a database connection To close ... you execute JPQL and JDOQL queries. To execute a query: Enter a query string. In the Parameters table

. The problem is that redeploying the application after that kind of usage of Explorer makes JPQL with Enum ... is that redeploying the application after that kind of usage of Explorer makes JPQL with Enum to don't work ... application. What happens when you run that JPQL query in the Explorer? In another Explorer? Try to bring

Hello I get an error when executing the following JPQL query: select doi from Doi doi left join ... with Oracle / MySQL / Postgres, so I'm assuming the JPQL is valid. Any ideas? Thanks John johnbrush John Brush The query is not a valid JPQL query since JOIN FETCH should be followed by a path

Possible issue for JPQL "LEFT [OUTER] JOIN" is doing "[INNER] JOIN".   Thanks. eurojet P. F. Martinez Thank you for this report. Please try build 2.3.7_18 that should fix this issue. support Support Great and fast solution but it doesn't work with the following JPQL queries string:  

and use persist() to write them to the database.  But does running a JPQL update or delete alter the in-memory objects? There are cases where the JPQL syntax is more expressive than operating

Hi, I have a case where I have a JPQL query like: "select o from MyEntity o WHERE (enumField IN :enumFieldList)" And enum field is defined in MyEntity as:     @Enumerated ... understood the JPA JPQL IN clause should work with Enum types - is that the case, or is this an objectdb

Is there a way to show the executed Sql/ Jpql in the console? wua Andreas Wurm You can set the log element in ObjectDB configuration to write logging also to the console:      ... / Jpql style not xml. I can only see select statements, but I also want to see insert, update

language for JPA is the Jakarta Persistence Query Language ( JPQL ). It enables you to retrieve objects from the database by using both simple and complex queries. JPA queries and JPQL are described in

Jakarta Persistence (JPA) provides a set of annotations to define and map native SQL queries when the standard Java Persistence Query Language ( JPQL ) is insufficient. While ObjectDB focuses on JPQL and ignores these annotations, they remain essential for applications interacting with relational

Jakarta Persistence (JPA) provides annotations to define static, reusable queries at the class level, separating query logic from business code. Query definitions Declare named queries using the following annotations: Specifies a static, named query in the Jakarta Persistence Query Language ( JPQL

, including aggregate queries, as part of its support of JPQL (JPA Query Language) and JDOQL (JDO Query Language). ObjectDB is faster than other products.

, criteria queries, and JPQL for data retrieval and manipulation. Describes the metamodel and graph APIs

A named query is a statically defined query with a predefined, unchangeable query string. Using named queries instead of dynamic queries can improve code organization by separating JPQL query strings from Java code. This practice also enforces the use of query parameters instead of embedding

processes JPQL (JPA Query Language) and JDOQL (JDO Query Language) queries directly, where ORM tools first

The Jakarta Persistence (JPA) Criteria API provides a type-safe, programmatic alternative to string-based JPQL for constructing dynamic queries, ensuring compile-time safety and facilitating easier refactoring. It defines a structured hierarchy of interfaces for SELECT, UPDATE, and DELETE

how to use the JPA Query Language ( JPQL ). Presents ObjectDB Tools: the Explorer, the Enhancer, the Doctor

the database. They are especially useful for deleting many entities in a single operation. For more information, see DELETE Queries in JPA/ JPQL .

, using two standard Java query languages: JPQL (Java Persistence Query Language) and JDOQL (JDO

The JPA Criteria API provides type-safe interfaces for defining query result expressions and ordering, mirroring the SELECT and ORDER BY clauses in JPQL or SQL. These interfaces allow you to specify exactly what data is returned and how it is sorted within the result set. SELECT clause elements

behavior. Declare static, reusable JPQL queries directly on the entity class. Optimize data retrieval by

when you must modify many entities in a single operation. The UPDATE Queries in JPA/ JPQL section in Chapter 4 explains how to use JPA UPDATE queries.

is reversed compared to the corresponding function in JPQL . Parameters: x - expression for string ... to the corresponding function in JPQL . Parameters: x - expression for string to be searched pattern - string ... function in JPQL . Parameters: x - expression for string to be searched pattern - expression for string

JPQL 2.0 introduces the ability define FROM variables for map keys and values. Currently ObjectDB supports FROM variables for collection elements. FROM variables for map keys and values are expected ... both KEY and VALUE statements with JPQL with the latest version of ObjectDB 2.3.7

JPQL (Java Persistence Query Language) supports updating and deleting database objects by queries. Currently ObjectDB supports only JPQL SELECT (retrieval) queries. Delete queries are supported for JDOQL (JDO Query Language). support Support spring-data-jpa uses delete queries to implement

this tutorial contains Point entities. We will use a simple JPQL query that retrieves points with x value in