Oracle TimesTen Reviews

What makes eXtremeDB platform independent? - Hybrid storage of data. Unlike other IMDS databases, eXtremeDB databases are all-in-memory or all-persistent. They can also have a mix between persistent tables and in-memory table. eXtremeDB's Active Replication Fabric™, which is unique to eXtremeDB, offers bidirectional replication and multi-tier replication (e.g. edge-to-gateway-to-gateway-to-cloud), compression to maximize limited bandwidth networks and more. - Row and columnar flexibility for time series data. eXtremeDB supports database designs which combine column-based and row-based layouts in order to maximize the CPU cache speed. - Client/Server and embedded. eXtremeDB provides data management that is fast and flexible wherever you need it. It can be deployed as an embedded system and/or as a clients/server database system. eXtremeDB was designed for use in resource-constrained, mission-critical embedded systems. Found in over 30,000,000 deployments, from routers to satellites and trains to stock market world-wide.

H2, the Java SQL database, is your welcome. An embedded mode allows an application to open a database within the same JVM by using JDBC. This connection mode is the fastest and most convenient. However, a database can only be opened in one virtual machine (and a class loader) at a time. Both in-memory and persistent databases are supported, as in all modes. There is no limit to the number of databases that can be opened simultaneously or the number of connections. Mixed mode is a combination between the server and embedded modes. The first application to connect to a database uses embedded mode. However, it also starts a server so other applications (running in different processes and virtual machines) can simultaneously access the same data. The local connections are just as fast as if the data were used in embedded mode. Remote connections are slightly slower.