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Function TrnGetTable - Slow Export

Sebastian

Is there a way to pull data faster using the trendgetable function?

When I call the trendgetable function, it takes a very long time before the function returns data from a longer period, e.g. several months.

For example, if I want to export data from a period of half a year every 2 hours for 5 variables, it takes 8 minutes before the function returns the data.

IF sTagColumn1 <> "!" THEN
ErrSet(1);
TrnGetTable("OBIEKT."+ sTagColumn1, TimestampToTimeInt(t1), Resolution_h ,REP_RANGE/Resolution_h, TrendTable1, 1 + 0 + 12 +0,0);
ErrSet(0);
END

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    When you request months of data, the trend server has to read a lot of samples from disk. You could make a duplicate trend tag (with a different name/file) that records at a much slower sample rate. Since you chose condense mode 12 (newest sample), it sounds like you don't care about all the in-between values so you wouldn't me missing anything by using a slower sample rate.

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  • 0

    When you request months of data, the trend server has to read a lot of samples from disk. You could make a duplicate trend tag (with a different name/file) that records at a much slower sample rate. Since you chose condense mode 12 (newest sample), it sounds like you don't care about all the in-between values so you wouldn't me missing anything by using a slower sample rate.

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