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Entry  17 Jan 2024, Francesco Renga, Forum, History tags 
    Reply  18 Jan 2024, Stefan Ritt, Forum, History tags 
       Reply  28 Jan 2024, Konstantin Olchanski, Forum, History tags 
Message ID: 2689     Entry time: 28 Jan 2024     In reply to: 2680
Author: Konstantin Olchanski 
Topic: Forum 
Subject: History tags 
> This part of the system has been designed by KO, so he should reply here.

That's right. Some of this stuff is historical gibberish that is no longer needed 
for FILE and SQL histories.

/History/Events is needed to create persistent mapping between history event names 
and history event id's (at some point history event id was same equipment event 
id, with the obvious problems when equipment event ids are duplicated, reused, 
renamed, deleted).

/History/Tags was used by the history editor to speed up "give me all tag names 
for this history event name". With the "MIDAS" history storage this required 
reading a lot of data from disk. With the "FILE" history and cached ZFS SSD, disk 
access is much cheaper and caching history event names and tags in odb is no 
longer necessary.

/History/Tags should probably be removed (be check that nobody uses it first).

/History/Events has to remain as long as "MIDAS" history storage is still used.

K.O.
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