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Points are missing from re-processed archives

Question asked by JamesGibb on Mar 31, 2015
Latest reply on Apr 10, 2015 by JamesGibb

Our PI system is 3.4.375.99 and upgrading is not on the cards just now so I'd like to find out what's happened in the following scenario.

 

The system is set to use auto-created archives, each 512MB in size.  These typically take a month or two to fill.

 

During the year points are added to the system, mostly without any backfilling of data (because they're added for new plant, etc. so there is no old data to put in)  At the end of the year, once the last archive that holds data for the year shifts on, we combine that year's archives into a single one from 1-1-XXXX to 31-12-XXXY using the archive subsystem offline tools.

 

This year (i.e. after the end of 2014) a handful of new points were created to take some lab results.  There was old data for these so back-filling was required.  The points were created before the offline merging of last year's archives.  The merging went along fine as usual and then the data was backfilled.  That data is present in the new, single year archive.

 

However, data for other points that were created during the previous year is missing.  Looking for it prior to 1-1-2015 just returns No Data.

 

It's definitely in the old auto-created archives; if they are re-registered in place of the big year long archive we can see the data.  So why is that data not incorporated into the combined big archive?

 

And how can we get it in there?

 

 

Cheers

 

James Gibb,

Ferrybridge 'C' Power Station, UK

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