Sybase Event Stream Processor complements traditional databases to help solve new classes of problems where continuous, event-driven data analysis is required.
Event Stream Processor is not a replacement for databases. Databases excel at storing and querying static data, and reliably processing transactions. However, databases are not effective at continuously analyzing fast moving streams of data.
Traditional databases must store all data on disk before beginning to process it.
Databases do not use preregistered continuous queries. Database queries are "one-time-only" queries. To ask a question ten times a second, you must issue the query ten times a second. This model breaks down when one or more such queries need to be executed continuously as polling the database faster results in a performance impact to the source systems. Additionally, the polling approach has latency.
Databases do not use incremental processing. Event Stream Processor can evaluate queries incrementally as data arrives.
Event Stream Processor is not an in-memory database. It shares some traits with in-memory databases in that it operates in and holds all data in memory, to achieve desired speed. However, unlike an in-memory database, that is designed to efficiently process on-demand queries, Event Stream Processor uses a data-flow architecture that is optimized for continuous event-driven queries.