Object Query Language
In today's world, Object Query Language has acquired significant relevance in various areas. Whether academically, professionally, or personally, Object Query Language has captured the attention of individuals of all ages and interests. From its impact on society to its influence on popular culture, Object Query Language has become a topic of widespread interest. In this article, we will explore the importance and scope of Object Query Language, as well as its implication in different aspects of daily life. From its origin to its evolution today, Object Query Language invites us to reflect on its meaning and its impact on the world in which we live.
 | This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages)
|
Object Query Language (OQL) is a query language standard for object-oriented databases modeled after SQL and developed by the Object Data Management Group (ODMG). Because of its overall complexity the complete OQL standard has not yet been fully implemented in any software. The OQL standard influenced the design of later query languages such as JDOQL and EJB QL, though none are considered to be any version of OQL.
General rules
The following rules apply to OQL statements:
- All complete statements must be terminated by a semi-colon.
- A list of entries in OQL is usually separated by commas but not terminated by a comma(,).
- Strings of text are enclosed by matching quotation marks.
Examples
Simple query
The following example illustrates how one might retrieve the CPU-speed of all PCs with more than 64MB of RAM from a fictional PC database:
SELECT pc.cpuspeed
FROM PCs pc
WHERE pc.ram > 64;
Query with grouping and aggregation
The following example illustrates how one might retrieve the average amount of RAM on a PC, grouped by manufacturer:
SELECT manufacturer, AVG(SELECT part.pc.ram FROM partition part)
FROM PCs pc
GROUP BY manufacturer: pc.manufacturer;
Note the use of the keyword partition, as opposed to aggregation in traditional SQL.
See also
- Object Data Management Group (ODMG)
- Object Definition Language
 | This software-engineering-related article is a stub. You can help Wikipedia by expanding it. |
 | This programming-language-related article is a stub. You can help Wikipedia by expanding it. |