"Slavcho Ivanov" <slavcho@gmail.com> writes:
> The query was as simple as possible
> "select * from data where "SensorID" = 18",
> and the result had a couple of rows where SensorID was NOT 18, but 3.
That's not too surprising if the index had gotten corrupted somehow,
but since you haven't provided any details that would let someone else
reproduce the problem, there's not much we can do with this report :-(
regards, tom lane