Indus-1 and Indus -2 Synchrotron Radiation Sources are third generation particle accelerators that accelerate electrons up to 450 MeV and 2.5 GeV respectively. This multi- accelerator complex requires various subsystems for its operations and maintaining beam stability. These sub-systems include Magnet Power supply, RF, Vacuum, Radiation monitoring, Beam Diagnostics, LCW etc. A minor perturbation in any of the subsystem parameters can degrade the performance and stability of electron beam. In order to correlate parameters of different sub-systems and to examine performance and process behaviour of Indus machines, this data needs to be logged in a central database. Thus data logging is a crucial element of Indus control System. The salient features of the data logging system are:

• Presently approximately 15,000 parameters values are being logged.
• All sub-systems parameters are logged at 1 Hz.
• The database schema is simplified to have only two types of tables , one for analog parameters and one for digital parameters.
• Last one hour data is maintained in separate table and older data in history table.
• Data logging application uses "bulk insertion" for logging data into database. For this per minute test file are generated.
• History data is made available on the website for Indus users. The data is formatted according to he configuration and provided to web though the stored procedures.
• Backup of the database is scheduled.