Object Oriented Databases Query by Attribute

Query by Attribute: Objectivity/DB has mechanisms similar to SQL for finding objects based on attribute. One can call “scan” functions that use predicates to find objects that fit specified criteria. The predicate language is similar to SQL and other query languages and the Objectivity/DB kernel will maintain user-definable b-tree indexes to optimize performance of these scans.

A fundamental difference from SQL, however, is that Objectivity/DB allows you to scope your search to a particular database or container, like looking for a file within a folder instead of looking through the entire disk.

You can narrow down the search because Objectivity/DB allows you to group objects logically rather than requiring that you group them by type in tables. Many objects have a principal organizing attribute beyond what kind of object it is. A bolt in a piece of machinery would likely be organized by its component. A company document would be organized by its project. A message would be organized by the date and time it was created.