Hi all, I want to have more discussions on the responses of selecting non-existent timeseries. Let's focus on the condition 2 - "select ZT1,ZT31 from root.demo" where root.demo.ZT1 doesn't exist. There can be 3 responses as follows. Response 1: reject service and return an error message. Response 2: provide service by neglecting "ZT1" and directly return the result table of "select ZT31 from root.demo". Response 3: provide service by returning the result table with fields under the column "root.demo.ZT1" being null. From my side, I definitely disapprove response 3 because of the possible confusion raised about the schema. My question is which one do you prefer, response 1 or response 2? I myself prefer response 2 to response 1, because response 2 not only conveys clearly the message that "root.demo.ZT1" doesn't exist, but also returns existent data. Sincerely, Lei Rui
On 9/26/2019 14:52????????????????????????<827011...@qq.com> wrote?? Hi~ I'm working on this issue and I think "both condition 2 and 3 should respond with error message" is better ------------------ ???????? ------------------ ??????: "Yuan Tian (Jira)"<j...@apache.org>; ????????: 2019??9??25??(??????) ????9:56 ??????: "dev"<dev@iotdb.apache.org>; ????: [jira] [Created] (IOTDB-240) query problem for iotdb filter EJTTianyu created IOTDB-240: ------------------------------- Summary: query problem for iotdb filter Key: IOTDB-240 URL: https://issues.apache.org/jira/browse/IOTDB-240 Project: Apache IoTDB Issue Type: Bug Reporter: EJTTianyu When querying a timeseries that does not exist, iotdb shows different behavior for SQL with or without filter. After starting a new iotdb instance, The following steps in iotdb-client below could reproduce the problem. Step 1: set storage group to root.demo Step 2: CREATE TIMESERIES root.demo.ZT31 WITH DATATYPE=INT64, ENCODING=RLE Step 3:insert into root.demo(timestamp,ZT31) values(1,1) when using sql: 1.select ZT1 from root.demo iotdb-client responds with message "Msg: Execute statement error: do not select any existing series" 2.select ZT1,ZT31 from root.demo iotdb-client responds with +-----------------------------------+--------------+ | Time|root.demo.ZT31| +-----------------------------------+--------------+ | 1970-01-01T08:00:00.001+08:00| 1| +-----------------------------------+--------------+ 3.select ZT1,ZT31 from root.demo where ZT1>0 iotdb-client responds with message "Msg: Execute statement error: Index: 0, Size: 0" Timeseries ZT1 does not exist in condition 2 and condition 3. However, without using ZT1 as filter to query multiple sensors(at least one exists), iotdb could respond with datapoints. When using ZT1 as filter, the returned msg confused users. In my opinion, both condition 2 and 3 should respond with message "Msg: Execute statement error: do not select any existing series". Or condition 2 responds with datapoints, condition 3 responds with "Msg: Execute statement error: do not select any existing series". -- This message was sent by Atlassian Jira (v8.3.4#803005)
