Hello,
Is there an easy way to get the last timestamped record not later than a
given date/time?
I record data for a scientific application and I do not sample my data
at a given, fixed frequency. Instead, whenever a physical value changes
beyond a given threshold, I get a new timestamped value which is stored
in the database.
For data analysis however it is more convenient to have a
regularly-spaced timeseries of that data. For instance, if I get
temperature measurements at 7:56, 8:02, 8:13 and 8:27, and would like a
timeseries 15-minutes apart (8:00, 8:15, 8:30), I would like MySQL to
automatically figure out that I need the measurements from 7:56, 8:13
and 8:27.
Any simple way to do that would be immensely appreciated.
Thanks in advance,
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David Lindelöf
Station 18
LESO-PB/EPFL
1015 Lausanne
tel +41-21-693.5556
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e-mail david.lindelof@stripped
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"We came. We saw. We kicked its ass."
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