Quite recently, I visited the SQLStream. As the majority of database server vendors, SQLStream is located in California; in San Francisco to be more precise. Of course, their primary product (also called SQLStream) supports the database language SQL, and they try to follow the SQL standard as much as possible. So far, nothing new under the sun. You would almost think that this is again one of many new vendors trying to dethrone Oracle, Microsoft, and IBM. However, that would be an incorrect assumption.

As the name implies, SQLStream is a so-called streaming database server, comparable to IBM InfoSphere Streams and StreamBase Server. The main difference between SQLStream on one hand and most other products on the other hand, is that the former is a pure SQL-based product. The statements to stream are according to the SQL standard. Most other streaming products use proprietary languages, such as Spade, or use extensions.

 
For those who haven't studied this topic in detail yet, a streaming database server allows us to formulate queries on streams of data. Examples of streams are log files of certain systems, messages that are entered, or web logs. Even before this data is stored in tables, we can already access them and analyze the data. Someone once explained streaming database servers as follows: queries executed in the context of a classic database server are like: how many fishes live in this pond, whilst queries executed in the context of a streaming database server  is like: how many fishes swim by in a fast-flowing river during a certain period of time.

SQLStream offers all the features above. In addition, views are used to define streams, and this type of streaming views can serve as input for other streaming views. Through join and union operators, data of different sources can be integrated. In fact, SQLStream supports many of the features normally found in an ETL tool, except that SQLStream uses streams and SQL. Data streams are integrated live the moment they arrive. The result of an integrated stream can be send to an application or data warehouse. See the following link that contains an explanation on how SQLStream can be used together with SQL Power.

In short, SQLStream is absolutely worth studying.

Note: The owners of SQLStream are also the founders of Eigenbase.org. This organization supplies a toolset with which database servers can be developed. As can be expected, SQLStream is also developed with this toolset.