MySQL Bugs: #29927: no database selected

Bug #29927	no database selected - sometimes
Submitted:	20 Jul 2007 10:36	Modified:	26 Jul 2007 7:06
Reporter:	Mauro Bernardini	Email Updates:
Status:	Can't repeat	Impact on me:	None
Category:	MySQL Server: Errors	Severity:	S1 (Critical)
Version:	5.2.1	OS:	Windows (Windows 2000)
Assigned to:		CPU Architecture:	Any
Tags:	no database selected - sometimes

Description:
I have the problem with "no database selected" but it appears sometimes. Great part of access with the web site tu the db MySQL works correctly. But sometimes appears this error message. It needs to refresh page or turn back and access again to the same page and, then, it works. May the my.ini configuration have some problem?
The system works on server with Windows 2000. DB is no so big and the max access number is about 100. Thanks 

How to repeat:
when launch the PHP string:

$conn = mysql_pconnect($hostname, $username, $password) or trigger_error(mysql_error(),E_USER_ERROR);

Thank you for the report.

I see you use connect string $conn = mysql_pconnect($hostname, $username, $password) which does not contain default database. Please check your application if mysql_select_db of mysql_query('USE db') were issued before you run a query which needs a database to be selected.

If you are sure in above create PHP script which we can run in our environment and repeat the error.

Sorry i forgot to include an important string:

mysql_select_db($database) or die("Non riesco a selezionare il db");

But as i wrote before the problem appears sporadically. The great part of times it connects correctly

Thank again

Thank you for the feedback.

Are you sure mysql_select_db($database) was running before every query which needs default database? To check it replace mysql_pconnect with mysql_connect and examine how MySQL server will behave.

Also version 5.2.1 looks like version of PHP. Which version of MySQL do you use?

I already replaced "mysql_pconnect" with "mysql_connect" ma it was the same thing.

My configuration is PHP 5.2.1 - Apache 2.2.4 - MySQL 5.0.22.

Yesterday I discovered in server log a problem relative to mysql like this:
Warning EventID:100 - Changed limits: max_open_files: 2048 max_connections:800 table_cache:619.

...then i changed this values in my.ini with:
max_connections=100;
table_cache=620

...and in this way it seems resolved because now I don't found anymore error logs and program run regularly. What other can i configured? Because i don'find "max_open_files". Thanks

Thank you for the bug report. Could you please upgrade to latest released
version 5.0.45 since your reported version is pretty older. Thanks in
advance.

I'll do it immediatly - Many thanks

Status cahnged, because feedback is needed.

Sorry but I didn't understand the "Status changed". What should I do exactly? Where I have to subscribe feedback? Please help me - thanks.

You should upgrade MySQL to version 5.0.45 and try with it.

Upgrade and test, then comment here the result.

Ok I upgraded and resolved succesfully (no more problems matched) but, I suppose, the problem was not depending by the upgrade. I found a wrong configuration on MY.INI file, as i wrote on 20 Jul 07 14:47. Thanks

Thank you for the feedback.

Report closed as "Can't repeat" because last comment