Bug #83925 DB collation changed to default after upgrade

• Submitted: 23 Nov 2016 7:40
• Modified: 5 Jan 2017 18:23
• Reporter: Abhishek Ranjan
• Status: Closed
• Category: MySQL Server: Data Dictionary
• Severity: S3 (Non-critical)
• Version: 8.0.1
• OS: Any
• CPU Architecture: Any

[23 Nov 2016 7:40] Abhishek Ranjan

Description:
The character set and collation mentioned in db.opt file is NOT used and
default character set is always used while upgrading schema.

How to repeat:
i> Initialize a database using 5.7 server
ii> Start 5.7 server on the data directory and create
    a few databases using non default collation

    create database db_koi8 character set='koi8r' collate='koi8r_general_ci' ;
    create database db_big5 collate='big5_bin';

iii> Show shutdown 5.7 server
iv> Start 8.0 server on same data directory
v>  Execute
    show create database db_koi8r;
    SELECT * from information_schema.schemata;

Observe the default character set name and collation name.
    

Suggested fix:
Correct default character set and collation name should be
upgraded to dictionary from db.opt file.

[27 Nov 2016 9:20] Simon Mudd

Related to: bug#83461

[5 Jan 2017 18:23] Daniel Price

Posted by developer:
 
Fixed as of the upcoming 8.0.1 release, and here's the changelog entry:

The default character set and collation were used instead of the
character set and collation defined in db.opt file when upgrading the
schema from MySQL 5.7 to MySQL 8.0.

[9 Jan 2017 7:19] Simon Mudd

Thanks. That's good to see this fix as it caused me a few breakages on some machines, and that should go away now.