Bug #13913 Can't specify ft_boolean_syntax in my.cnf
Submitted: 11 Oct 2005 7:19 Modified: 13 Oct 2005 14:05
Reporter: Michael K Email Updates:
Status: Closed Impact on me:
Category:MySQL Server: Documentation Severity:S2 (Serious)
Version:4.0.26 OS:Linux (Fedora Core 3)
Assigned to: Paul Dubois CPU Architecture:Any
Triage: D4 (Minor)

[11 Oct 2005 7:19] Michael K

I'm trying to customize the fulltext boolean syntax. Mysql manual states I can change it by specifying ft_boolean_syntax variable in my.cnf. It doesn't really work.

How to repeat:
Add this line to [mysqld] section:

ft_boolean_syntax=\'+ -><()~*:""&|\'

Start mysql, observe this in .err file:
051011  1:59:49 /usr/sbin/mysqld: unknown variable 'ft_boolean_syntax='+ -><()~*

Any value I've tried is rejected in the same way.
[11 Oct 2005 7:27] Michael K
Trying to change it from the mysql client prompt:

mysql> set global ft_boolean_syntax='+ -><()~*:""&|';
ERROR 1193: Unknown system variable 'ft_boolean_syntax'

mysql> show variables like 'ft_boo%';
| Variable_name     | Value          |
| ft_boolean_syntax | + -><()~*:""&| |

Googling reveals another report about this problem:
[11 Oct 2005 8:45] Valeriy Kravchuk
Thank you for a problem report. Please, try to use newer version, 4.0.26. Inform about the results.

I see nothing about the FULLTEXT support in the changes of this release, but just to be sure.
[11 Oct 2005 9:10] Michael K
It doesn't work in 4.0.26 either, not through my.cnf nor via "set global ft_boolean_syntax=..".
[12 Oct 2005 13:03] Sergei Golubchik
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.mysql.com/documentation/ and the instructions on
how to report a bug at http://bugs.mysql.com/how-to-report.php

Additional info:

See http://dev.mysql.com/doc/refman/4.1/en/news-4-1-2.html

The ft_boolean_syntax variable now can be changed while the server is running. See Section 5.2.3, “Server System Variables”.
[12 Oct 2005 13:37] Michael K
I beg to differ. What's the changing of ft_boolean_syntax while the server is running have to do with original scope of this bug (specifying ft_boolean_syntax in my.cnf)? Are you saying that I can't change ft_boolean_syntax even through my.cnf? What's the point of having this variable then?

From one of your docs' mirrors:

    The list of operators supported by boolean full-text searches performed using IN BOOLEAN MODE. This variable was added in MySQL 4.0.1. See section 13.6.1 Boolean Full-Text Searches. The default variable value is '+ -><()~*:""&|'. The rules for changing the value are as follows: ...

I see that you removed this reference to version 4.0.1 from the docs on your main site. Is it a hint that this bug won't be fixed?
[12 Oct 2005 14:18] Sergei Golubchik
No, it was not a hint, probably an unrelated change.

No, it won't be fixed - in 4.0 ft_boolean_syntax was a read-only server variable, not even a command-line option. It became writable in 4.1.

But I agree it could be documented better.
[13 Oct 2005 14:05] Paul Dubois
Thank you for your bug report. This issue has been addressed in the
documentation. The updated documentation will appear on our website
shortly, and will be included in the next release of the relevant

Additional info:

I'll update the description for ft_boolean_syntax to point
out that it's read-only before 4.1.2.