A lightcurve is a history of the brightness of a source, and is built from multiple detections of that source. From a lightcurve, we wish to compute features, some simple such as min/max magnitude, magnitude slope, most recent magnitude, etc, and some more complex, such as periodicity, machine-learning classifications, etc. In general, it is these features that go into user-built queries, rather than asking about individual detections.
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