MCS TO ONLINE DATABASE RECORDS

Preliminary version 0.2, Sam Segler, John Yoh, 1/27/99

There is some interest in recording data read from the various MCS systems in the CDF online database so that it can be accessed later offline by using PAW, ROOT, or the offline package. Some of the motivations for this are :

• Better bookkeeping, allowing the detector expert to get a history of the system of interest. Charts, tables, statistics including variances and excursions, can be obtained.
• In case of suspect data, one can check the voltages/current/etc. info during the period when the suspect data was taken.
• Potential for automatic search for suspect voltages, etc. to tag datasets

The current plan, subject to user and system expert demands, is to record all setting values once per day (or at the time any changes were made) plus periodically (every 10 to 30 minutes) record the readings from all channels. As an estimate, 25,000 channels of information, occupying 6 bytes each, recorded every 30 minutes would result in 3GB per year, not an unmanageable amount of disk space.

Currently (Jan 1999), two efforts are underway.

• Don Walsh of the Fermilab CD is testing writing to an Oracle database using the FIX/Dynamic-provided method.
• Larry Kirsch from Brandeis U. is testing writing directly to an Oracle database using VB code.

Writing to Oracle On-line Database - Don Walsh Writeup

Currently (April 2000) Margherita Vittone of the CD is starting work on implementing a Java application that would access a list of tags from each iFIX database and write them to various tables in the Oracle on-line database. This effort is just beginning. As a first example, there is a proposal from Rick StDenis for an Oracle Table Structure.