I'm looking back at history data tables and I noticed that some older tables (e.g. from before Nov 2023) were querying in 50s instead of <1s, and found that there was no clustered index on the tagid and t_stamp fields like there are in later tables. I note this note in the user manual, but there's no mention of when it was added. Was it something that was changed? or did these old tables just get corrupted or something? (these tables were copied to an AWS archive database by the end users's IT, so I have no control or knowledge of what they did)
Note: the system has been upgraded numerous times over the years so I'm not sure if there was a version upgrade in nov 2023
IIRC, indexes were not always included. I remember seeing somewhere on the forums where it was suggested that the end user needed to add indexes to improve performance.
I don't know if I ever did this, but definitely the data tables for 2024 and 2025 all have them and I certainly haven't added them myself. That's why I presumed it was maybe changed in a version. It seems a bit crazy that the tables wouldn't have indexes though... if you have 700,000,000 records it's kind of a necessity! (and not something an integrator should need to add)
Well, here is a post where I was clearly positive that they were not there by default in 7.9.
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