Character set 'utf-8' is not a compiled character set and is not specified in the '/usr/share/mysql/charsets/Index.xml' file

Question

We are trying to upgrade our MediaWiki software. According to Manual:Upgrading -> UPGRADE -> Manual:Backing_up_a_wiki, we are supposed to backup the database with:

mysqldump -h hostname -u userid -p --default-character-set=whatever dbname > backup.sql

When we run the command with our parameters and --default-character-set=utf-8:

$ sudo mysqldump -h localhost -u XXX -p YYY --default-character-set=utf-8 ZZZ > 
backup.sql
mysqldump: Character set 'utf-8' is not a compiled character set and is not spec
ified in the '/usr/share/mysql/charsets/Index.xml' file

Checking Index.xml appears to show utf-8 is available. UTF-8 is specifically called out by Manual:$wgDBTableOptions.

$ cat /usr/share/mysql/charsets/Index.xml | grep -B 3 -i 'utf-8'
...
<charset name="utf8">
  <family>Unicode</family>
  <description>UTF-8 Unicode</description>
  <alias>utf-8</alias>
...

We tried both UTF-8 and utf-8 as specified by Manual:$wgDBTableOptions.

I have a couple of questions. First, can we omit --default-character-set since its not working as expected? Second, if we have to use --default-character-set, then what is used to specify UTF-8?

---

A third, related question is, can we forgo mysqldump all-together by taking the wiki and database offline and then making a physical copy of the database? I am happy to make a copy of the physical database for a restore; and I really don't care much for using tools that cause more trouble than they solve.

If the third item is a viable option, then what is the physical database file that needs to be copied?

Answer 1

I had the same problem:

ERROR: Unable to start MySQL server:
mysqld: Character set 'UTF-8' is not a compiled character set and is not specified in the '/usr/share/mysql/charsets/Index.xml' file
mysqld: Character set 'UTF-8' is not a compiled character set and is not specified in the '/usr/share/mysql/charsets/Index.xml' file

I edited the mysqld.cnf and changed

character-set-server = UTF8

to

character-set-server = utf8mb4

Answer 2

In my case It was the same command but I did not need to change the conf file, and the command --default-character-set indeed does work. It is a bug with MySQL, just change "utf-8" to "utf8" or even "utf8mb4" for MySQL.

Answer 3

First, can we omit --default-character-set since its not working as expected?

We took the first option and the upgrade proceeded. You mileage may vary.