TechView Product Report: ObjectStore - ODBMS

Microsoft .NET Common Runtime (CLR). Customers will be able to write Microsoft
.NET applications that execute within the .NET CLR and can directly access
ObjectStore’s C++ interface. ObjectStore C++ databases will be concurrently
accessible from both managed and unmanaged C++ applications.
Queries
2. Does your product support querying? If yes, can you describe the querying
mechanism, giving examples of queries?
Yes, ObjectStore supports a variety of means to access data.
ObjectStore provides a query mechanism across all provided collection classes.
The C++ interface provides sets, bags, lists, dictionaries. The Java interface
provides support for the JDK collection types.
Queries are most commonly submitted as textual expressions to the query processor
as part of the support API. The expressions allow users to return a particular set of
objects where the set is restricted based on a variety of user supplied qualifications.
Users can use Boolean expression that restrict on data member values, member
function returns and can extend expression on data found through or simply the
existence of relationship with other instances (of any class). Queries can also be
precompiled for optimization and reuse. Queries will also optimize execution based
on the existence of indexes as well.
ObjectStore also provides support for queries across type extents as well. We support
an optimization to quickly determine the minimal set of pages in the database that
contains instances of type to be searched.
ObjectStore also supports an Xpath. Customers can now submit through a utility or
API Xpath expressions that will return a qualified XML representation of the
database. Again the existence of indexes will be utilized wherever the index applies to
the qualifications in the Xpath expression.
3. How is your query language different from SQL?
SQL provides a non procedural mechanism for finding data. It allows both restriction
and projection. ObjectStore’s query mechanism can also provide a non procedural
means of accessing and restricting data but the restrictions are much more directed
in terms of the data model. SQL will require users to materialize relationships, in
essence create them as part of the query expression. ObjectStore maintains the users
data model from the desired in memory representation all the way through to the
persistent storage model. All the relationships stay constructed and are available as
part of the query syntax and its direct execution.
Probably the most important thing to understand is ObjectStore will basically give
you the ability to utilize the natural structure and behavioral model associated with
data. Typical implementations of SQL are far more restricted on supported data
models, usually boiling down to some representation of a relation as a table.
It is not realistic to represent the simplest form of some common data structures as
tables, even a linked list can be complicated never mind something more advanced
like a tree or a graph. If you compromise your data model then you compromise your
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