RDBArchiveEngine

= RDB Archive Engine =

Fundamentally, the !ArchiveEngine operates as the previous Channel Archiver's Archive Engine did, so the manual on https://ics-web.sns.ornl.gov/kasemir/archiver/index.html still has some relevance.

Differences:

• Implemented in Java (CSS, Eclipse) instead of C++
• Writes to RDB (Oracle, MySQL, maybe soon Hyper Table) instead of the binary data files used by the Channel Archiver
• Configured from RDB instead of XML files

== Configuration Details ==

Compared to the Channel Archiver, the configuration options of the RDB Archive Engine has a few differences:

=== Enable/Disable === The old engine supported 'disabling' channels, while the new engine supports 'enabling' channels. The meaning is exactly reversed, because the positive 'enabling' seemed easier to understand than the negative 'disabling'.

=== Monitor === Works as before, and it's use is strongly encouraged.

=== Scanned Mode === The 'get_threshold' is no longer used. Scanned channels are always internally based on monitors. Since scanned operation is usually either missing short value changes or needlessly scanning the same unchanged value, you are strongly encouraged to use Monitored operation with an appropriate ADEL on the IOC side.

If the IOC cannot be configured with a suitable ADEL, the sample engine itself can now perform the deadband check via the "smpl_val" parameter.