Bug #46393 If for slow_query_log a string is entered it does not complain.
Submitted: 27 Jul 2009 8:51 Modified: 29 Jan 2011 23:17
Reporter: Oli Sennhauser Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Options Severity:S3 (Non-critical)
Version:5.1.36 OS:Any
Assigned to: Alexey Botchkov
Tags: slow_query_log
Triage: Triaged: D3 (Medium)

[27 Jul 2009 8:51] Oli Sennhauser
Description:
If in the my.cnf the parameter slow_query_log was wrongly specified (it should be correctly either slow_query_log_file OR log_slow_queries) for example as a string as follows:

# my.cnf
slow_query_log = slow.log

The slow query log is NOT created NOR any warning about a problem is written to the error.log

How to repeat:
Start MySQL with:

# my.cnf
slow_query_log = slow.log

Suggested fix:
Report an error in the error.log that the variable was specified wrongly.
[14 Jan 2011 23:21] Alexey Botchkov
The testcase is problemmatic here.
That thing manifests only with the warning in the server errorlog if the boolean option in the config file or command line specified incorrectly.
[14 Jan 2011 23:22] Bugs System
Pushed into mysql-5.5 5.5.10 (revid:holyfoot@mysql.com-20110114221822-3jz165arzflboxsb) (version source revid:holyfoot@mysql.com-20110114221822-3jz165arzflboxsb) (merge vers: 5.5.10) (pib:24)
[14 Jan 2011 23:25] Bugs System
Pushed into mysql-trunk 5.6.2 (revid:holyfoot@mysql.com-20110114222238-ora0koaemxb178ue) (version source revid:holyfoot@mysql.com-20110114222238-ora0koaemxb178ue) (merge vers: 5.6.2) (pib:24)
[18 Jan 2011 20:30] Paul Dubois
Noted in 5.5.10, 5.6.2 changelogs.

Boolean system variables can be enabled at run time by setting them
to the value ON or OFF, but previously this did not work at server
startup. Now at startup such variables can be enabled by setting them
to ON or TRUE, or disabled by setting them to OFF or FALSE. Any other
nonnumeric variable is invalid.