Description:
Manual (http://dev.mysql.com/doc/refman/5.6/en/innodb-parameters.html#sysvar_innodb_ft_enable_diag...) says that this variable has default value ON since 5.6.7. But this is wrong for 5.6.15 on Windows at least:
mysql> set global innodb_ft_enable_diag_print=DEFAULT;
Query OK, 0 rows affected (0.00 sec)
mysql> show global variables like 'innodb_ft_ena%';
+-----------------------------+-------+
| Variable_name | Value |
+-----------------------------+-------+
| innodb_ft_enable_diag_print | OFF |
| innodb_ft_enable_stopword | ON |
+-----------------------------+-------+
2 rows in set (0.00 sec)
mysql> show variables like '%version%';
+-------------------------+------------------------------+
| Variable_name | Value |
+-------------------------+------------------------------+
| innodb_version | 5.6.15 |
| protocol_version | 10 |
| slave_type_conversions | |
| version | 5.6.15-log |
| version_comment | MySQL Community Server (GPL) |
| version_compile_machine | x86_64 |
| version_compile_os | Win64 |
+-------------------------+------------------------------+
7 rows in set (0.00 sec)
It's OFF by default.
Now, all manual says about the effect of this variable is:
"Whether to enable additional full-text search diagnostic output."
This statement is absolutely useless, one could infer that from variable name.
What kind of output is it? Where one should expect this output? All these things are important and they are missing.
How to repeat:
set global innodb_ft_enable_diag_print=DEFAULT;
show global variables like 'innodb_ft_ena%';
show variables like '%version%';
Suggested fix:
Make sure that manual does not only list some variable, but that type, range of acceptable values and default value are explained correctly and all effects of the variable are described.
