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In select into statement, default encoding type may cause compatibility problems

Open nlosilva1 opened this issue 3 years ago • 0 comments

Describe the bug

  1. In the documentation, GORILLA encoding type has a restriction. However, some select into statements will automatic create a timeseries with GORILLA encoding type(while the original timeseries is not a GORILLA type), which may be conflict with GORILLA's restriction. If we can't change the default encoding type in select...into... clause, this problem may exist. Perhaps there will be other conficts in this select...into... clause.
  2. I try to insert a -Double.MAX_VALUE point into the database, with other points all positive, which means the sum will not over Double; but it still returns -Infinity while I use a avg agggregation statement with group by.

To Reproduce

  1. running the following iotdb-sql in iotdb-client: SET STORAGE GROUP TO root.sg0; CREATE TIMESERIES root.sg0.t1 WITH DATATYPE=DOUBLE, ENCODING=PLAIN; INSERT INTO root.sg0(timestamp, t1) VALUES (9603, 0.732498412173562); INSERT INTO root.sg0(timestamp, t1) VALUES (12492, 0.885314087043015); INSERT INTO root.sg0(timestamp, t1) VALUES (39503, 0.08816170378111365); INSERT INTO root.sg0(timestamp, t1) VALUES (25965, -1.7976931348623157E308); INSERT INTO root.sg0(timestamp, t1) VALUES (78893, 0.47220064168506504); select t1 into t0 from root.sg0 select avg(t1),avg(t0) from root.* group by([1000, 100000), 40000ms)

Expected behavior

  1. There will be a -Double.MAX_VALUE in a GORILLA type timeseries(root.sg0.t0), which might be invalid? (I think there will also be a restriction in GORILLA while using Double datatype, but the document doesn't mention it)
  2. There will be no Infinity exists in the result, since all single points are in the range of double, (though there is a point has a value of -Double.MAX_VALUE)

Screenshots This is the result of the last query, which has -Infinity. image

This avg aggregation return -Infinity, while some other range of group by / sum aggregation will not return infinity. 1660181660436 image

The encoding of t0 becomes GORILLA image

  • OS: Windows 10
  • Version: iotdb 0.13.1

nlosilva1 avatar Aug 11 '22 01:08 nlosilva1