Recent developments and object-oriented approach in FTU database

Abstract During the last two years, the experimental database of Frascati Tokamak Upgrade (FTU) has been changed from several points of view, particularly: (i) the data and the analysis codes have been moved from the IBM main frame to Unix platforms making enabling the users to take advantage of the large quantities of commercial and free software available under Unix (Matlab, IDL, …); (ii) AFS (Andrew File System) has been chosen as the distributed file system making the data available on all the nodes and distributing the workload; (iii) ‘One measure/one file’ philosophy (vs. the previous ‘one pulse/one file’) has been adopted increasing the number of files into the database but, at the same time, allowing the most important data to be available just after the plasma discharge. The client–server architecture has been tested using the signal viewer client jScope . Moreover, an object oriented data model (OODM) of FTU experimental data has been tried: a generalized model in tokamak experimental data has been developed with typical concepts such as abstraction, encapsulation, inheritance, and polymorphism. The model has been integrated with data coming from different databases, building an Object Warehouse to extract, with data mining techniques, meaningful trends and patterns from huge amounts of data.