Grouper Developers Forum

[Scott Koranda <>]

Hi,

> 
> MYSQL UTF8 issue 
> 
> https://mathiasbynens.be/notes/mysql-utf8mb4
> 
> There are cases where things don’t work
> 
> Chris suggests we change documentation to recommend utf8mb4
> 
> https://dev.mysql.com/doc/refman/5.5/en/charset-unicode-utf8mb4.html
> 
> Suggestion to use this utf8mb4 approach in testing to be sure it works 
> before
> we recommend it.

My testing with Grouper 2.2.2 shows that one cannot yet
recommend the use of utf8mb4 and for now the Grouper project
should recommend for MySQL/MariaDB

character-set-server = utf8
collation-server = utf8_bin

The reason is explained in this StackOverflow post:

http://stackoverflow.com/questions/1814532/1071-specified-key-was-too-long-max-key-length-is-767-bytes

In short, the database engines in MySQL/MariaDB that support
transactions have limitations on the length of prefixes for
indices. For InnoDB and XtraDB, the prefix is limited to 767
bytes. When using utf8mb4, where 4 bytes are used instead of
2, the prefixes used for some Grouper tables are too long.

If somebody finds otherwise, please let me know. For now I am
deploying Grouper using 

character-set-server = utf8
collation-server = utf8_bin

when using MySQL/MariaDB as the backend.

Thanks,

Scott K