Note:
This topic has been translated from a Chinese forum by GPT and might contain errors.Original topic: ifnull好像触发bug了
|
username: qhd2004
[TiDB Version]
v5.4.1
[Encountered Problem: Phenomenon and Impact]
ifnull function works in this query.
ifnull function seems incorrect in this query. Is it triggering a bug?
Attached are two tables dumped using mysqldump.
syk_test.sql (27.1 KB)
The two SQL queries provided are selecting values from subqueries and using the IFNULL function to handle null values. The first query is selecting from a subquery named a which retrieves measure_status and the value of measure_status lagged by 2 rows within each patient_id partition, ordered by create_time. The second query is similar but selects from a subquery named b, which retrieves measure_status and the value of measure_status lagged by 2 rows within each patient_id partition, ordered by measure_time. Both queries replace null values with ‘-1’ using the IFNULL function.
Why wasn’t null captured? Using case when or if(xx is null, ‘-1’, l2), is there a difference between them?
关注了
During testing, it was found that it works in version V6.3.0.
Please have the official team check if it is a bug.
It is also possible that this BUG exists in some older versions but has been fixed in the new version.
I think we can raise an issue. This is an unexpected behavior. 
This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.
|
username: 
|
username: 
|
username: 
|
username: 
|
username: