Speaker
Dr
Julius Hrivnac
(LAL)
Description
Efficient and friendly access to the large amount of data distributed
over the wide area network is a challenge for the near future LCG experiments.
The problem can be solved using current standard open technologies and tools.
A JDBC standard solution has been chosen as a base for a comprehensive
system for the relational data access and management. Widely available
open tools have been reused and extended to satisfy HEP needs.
- An SQL backend has been implemented for the Abstract Interface for Data Analysis
(AIDA), making relational data available via standard analysis API.
Interfaces to several languages, plugins to Java Analysis Studio as well
as Web Service access are available and interfaced with Atlas Event Metadata
(Tag) database.
- Clustered JDBC (C-JDBC) from ObjectWeb Consortium has been reused to enable
transparent and optimized access to distributed relational database. Two
extensions have been developed:
- Query splitter, which sends a user query to a set of complementary
databases and delivers the merged result back to the user.
- Predictive Query engine, which uses monitoring and caching information
to deliver fast approximative answer to time-consuming SQL queries.
- Octopus replication tool from ObjectWeb Consortium has been extended
with specific requirements of the Atlas experiment and used to replicate
Atlas data over heterogeneous database network.
Primary author
Dr
Julius Hrivnac
(LAL)
