Bug #96620 The CONVERT_TZ function fetches wrong value for "Asia/Irkutsk" timezone
Submitted: 22 Aug 2019 13:14 Modified: 24 Sep 2019 11:41
Reporter: Jitender Yadav Email Updates:
Status: Can't repeat Impact on me:
None 
Category:MySQL Server: Data Types Severity:S2 (Serious)
Version:5.6.10 OS:Any
Assigned to: CPU Architecture:Any

[22 Aug 2019 13:14] Jitender Yadav
Description:
The timezone offset of 'Asia/Irkutsk' is UTC+8 and there's is no daylight savings time applicable for this timezone. Though mysql still returns results considering "'Asia/Irkutsk'" timezone to be under daylight savings.

Take the following two examples:

Example 1:
select CONVERT_TZ('2019-10-21 10:00:00.0','UTC', 'Asia/Irkutsk') 

Result:    2019-11-21 19:00:00.0
offset: UTC+9

Example2:
select CONVERT_TZ('2019-11-21 10:00:00.0','UTC', 'Asia/Irkutsk') as end_time;

Result:   2019-11-21 18:00:00.0
offset: UTC+8

In the above case mysql is considering 'Asia/Irkutsk' to be a daylight savings city which is not the case now but earlier it used to have daylight savings

Please get this corrected

How to repeat:
Example 1:
select CONVERT_TZ('2019-10-21 10:00:00.0','UTC', 'Asia/Irkutsk') 

Result:    2019-11-21 19:00:00.0
offset: UTC+9

Example2:
select CONVERT_TZ('2019-11-21 10:00:00.0','UTC', 'Asia/Irkutsk') as end_time;

Result:   2019-11-21 18:00:00.0
offset: UTC+8
[23 Aug 2019 12:41] MySQL Verification Team
Hello Mr. Yadav,

Thank you for your bug report.

Your release 5.6.10 is ancient. Please try 5.7.27 or 8.0.17 and let us know if they behave correctly.

5.6.10 was released during the time when your city had daylight saving timezone.
[24 Sep 2019 1:00] Bugs System
No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".