MySQL Bugs: #18209: mysqldump: ignoring option '--databases' due to invalid value 'xcc'

Bug #18209	mysqldump: ignoring option '--databases' due to invalid value 'xcc'
Submitted:	14 Mar 2006 8:04	Modified:	5 Dec 2008 8:40
Reporter:	Olaf van der Spek (Basic Quality Contributor)	Email Updates:
Status:	Closed
Category:	Client	Severity:	S3 (Non-critical)
Version:	5.0.18	OS:	Linux (Debian)
Assigned to:	Magnus Blaudd	Target Version:

Description:
Hi,

I added database = xcc to .my.cnf and now I get warnings from mysqldump. I think
mysqldump should ignore .my.cnf - database when a database has been given on the command
line

How to repeat:
.my.cnf:
[client]
user = xcc
password = *
database = xcc

$ mysqldump -u xcc xcc <lots of tables>
mysqldump: ignoring option '--databases' due to invalid value 'xcc'

verified using "database = mysql" in .my.cnf

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:

The "--databases" argument to mysqldump(and other mysql tools) is a flag indicating that
_all_ the name arguments on the command line should be treated as database names. It's
thus working as expected. 

See this section in the manual http://dev.mysql.com/doc/refman/5.0/en/mysqldump.html and
the below descripton

"--databases, -B

Dump several databases. Normally, mysqldump treats the first name argument on the command
line as a database name and following names as table names. With this option, it treats
all name arguments as database names. CREATE DATABASE and USE statements are included in
the output before each new database. "

> The "--databases" argument to mysqldump(and other mysql tools) is a flag
indicating that _all_ the name arguments on the command line should be treated
as database names. It's thus working as expected. 

Who's talking about --databases?

Got it. Will have another look. Sorry for the confusion.

If I write "dat=xcc" in my.cnf that will be interpreted by mysqldump as I mean the
"--databases" argument and it will print the same error message.

Indeed, but mysqldump should ignore the value in my.cnf, at least in this case.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/6311

Any easy fix is otherwise to move the parameter "database=xyz" to the [mysql] section of
my.cnf as that section will only be read by mysql command line client.

It is by design possible to write the options on a short format if they are unambiguos.
Thus "--database=xyz" will be interpreted as "--databases" by mysqldump.

Has the patch made it to the main codebase yet?  My "mysql --version" outputs:

mysql  Ver 14.12 Distrib 5.0.32, for pc-linux-gnu (i486) using readline 5.2

... and it still has this problem.

Also, the error message seems to be wrong, or at least misleading.  It says "ignoring ...
due to invalid value" which implies that there exists a valid value.

Since the "--databases" option doesn't accept a valid database name, (I reasoned to
myself,) perhaps it is a boolean true/false flag.  So I tried setting it to an empty
string, numeric zero, and 'false'.  The empty string is reported to be invalid, and both
the numeric zero and 'false' are ignored as if they hadn't been specified.  That is, a
.my.cnf containing:

[client]
database=d6
[mysqldump]
databases=

... results in:

mysqldump: ignoreing option '--databases' due to invalid value ''

... and a .my.cnf containing:

[client]
database=d6
[mysqldump]
databases=0

... results in:

mysqldump: ignoring option '--databases' due to an invalid value 'd6'

... and a .my.cnf containing:

[client]
database=d6
[mysqldump]
databases=false

... also results in:

mysqldump: ignoring option '--databases' due to an invalid value 'd6'

Just read the previous posts and you'll see that mysqldump does not have a --database
option it's --databases - with an ending s! Then read the previous posts again ;) to
learn what --databases does.

> to learn what --databases does.

As you can see, it's confusing to users. A solution would be appreciated.