Yuan Tian created IOTDB-803: ------------------------------- Summary: Improve the way of applying aggregate func to same series in group by Key: IOTDB-803 URL: https://issues.apache.org/jira/browse/IOTDB-803 Project: Apache IoTDB Issue Type: Improvement Components: Core/Engine Reporter: Yuan Tian
Now, in group by, if we include more than one aggregate function for one series, we will iterate the series data as many times as the number of the aggregate functions. For example, select count(s1), sum(s1), avg(s1) from root.sg1.d1 group by([0, 100000), 10ms) Suppose that the batch data we get from s1 ranges from 0 to 20 While calculating the count(s1), we will iterate the batch data from 0 to 10. And then while calculating sum or avg, we will reset the cursor to 0, and iterate the batch data again. However, we can do count, sum and avg function simutaneously in one iteration while will be also good for cpu cache hit ratio. -- This message was sent by Atlassian Jira (v8.3.4#803005)