[SOLVED] QSqlDatabase: QMYSQL driver not loaded with QMYSQL driver available in OSX Mavericks

ucmar · wrote on 26 Dec 2013, 15:39

Hi all, I am having an issue with QMYSQL when open a project created in Qt4.7 in Qt5.2. In particular when connecting to the database, i get the following error:

@QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QMYSQL QMYSQL3 QODBC QODBC3 QPSQL QPSQL7@

I am using Qt5.2 on OSX 10.9.1 (Mavericks). Have any of you had any similar issue? Thank you.

Mario

SGaist · wrote on 26 Dec 2013, 20:41

Hi,

Do you have MySql installed on Mavericks ? If so run otool -L on the qmysql.dylib plugin to see if everything is correct

ucmar · wrote on 27 Dec 2013, 15:07

hi, I have no qmysql.dylib in ~/Qt5.2.0/5.2.0/clang_64/plugins/sqldrivers so I did:
@otool -L libqsqlmysql.dylib@
I don't know if this is what you meant.

The output is:
@libqsqlmysql.dylib:
libqsqlmysql.dylib (compatibility version 0.0.0, current version 0.0.0)
/opt/local/lib/mysql55/mysql/libmysqlclient.18.dylib (compatibility version 18.0.0, current version 18.0.0)
/usr/lib/libz.1.dylib (compatibility version 1.0.0, current version 1.2.5)
/Users/ucmar/Qt5.2.0/5.2.0/clang_64/lib/QtSql.framework/Versions/5/QtSql (compatibility version 5.2.0, current version 5.2.0)
/Users/ucmar/Qt5.2.0/5.2.0/clang_64/lib/QtCore.framework/Versions/5/QtCore (compatibility version 5.2.0, current version 5.2.0)
/usr/lib/libstdc++.6.dylib (compatibility version 7.0.0, current version 56.0.0)
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 169.3.0)@

Thanks.

SGaist · wrote on 27 Dec 2013, 21:40

You got the right name, sorry for the wrong direction. The output looks good. Can you post what error you have from the connection failure ?

ucmar · wrote on 27 Dec 2013, 22:50

So, I get a window with the text: "Driver not loaded Driver not loaded". The Application Output returns the following error:
@QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QMYSQL QMYSQL3 QODBC QODBC3 QPSQL QPSQL7
QSqlQuery::exec: database not open@

SGaist · wrote on 29 Dec 2013, 23:16

and what does QSqlDatabase::lastError() return ?

ucmar · wrote on 30 Dec 2013, 15:53

That function seems to return this text: “Driver not loaded Driver not loaded”.
I am using the following error check:
@if (!db.open())
{
QMessageBox::critical(0, QObject::tr("Database Error"),
db.lastError().text());
}@

SGaist · wrote on 30 Dec 2013, 16:30

Just to be sure do you have this file:

/opt/local/lib/mysql55/mysql/libmysqlclient.18.dylib ?

ucmar · wrote on 30 Dec 2013, 16:52

Thanks for your hint. I didn't have it, and I also missed the folder "../mysql". I have just tried to copy it from another folder on my mac (a subfolder of a drupal local website), but my application still shoots the same error... :(

SGaist · wrote on 30 Dec 2013, 21:10

Since it's in /opt/ I would suspect it's a MacPort install of MySql.

If you have the same lib you can use install_name_tool to change the path in your libqsqlmysql.dylib

ucmar · wrote on 31 Dec 2013, 01:17

Thank you very much SGaist!!! I realized I had mistakenly created only the "../mysql" folder under "/opt/local/lib"! I have then fixed my problem by creating the complete folder path "../mysql55/mysql" as you suggested and copying the file libmysqlclient.18.dylib there. My Database connection is correctly working now! :D

Wish you a great 2014! Eheh

Mario

SGaist · wrote on 31 Dec 2013, 21:26

You're welcome !

All the same to you !

foxgod · wrote on 27 Feb 2014, 02:15

my os is windows 7 ,andI am having an issue with QMYSQL when open a project in Qt5.2. In particular when connecting to the database, i get the following error:

QSqlDatabase: QMYSQL driver not loaded
QSqlDatabase :available drivers: QSQLITE QMYSQL QMYSQL3 QODBC QODBC3 QPSQL QPSQL7

SGaist · wrote on 27 Feb 2014, 10:24

Hi foxgod,

Please have a look at the already numerous threads related to this problem with windows. This one is dedicated to OS X.

cdallago · wrote on 2 Apr 2014, 15:38

Hi guys,
I'm sorry to open this post again but I found this to be the thread that best approximates my situation.

Basically I followed everything until here:
[quote author="SGaist" date="1388421018"]Just to be sure do you have this file:

/opt/local/lib/mysql55/mysql/libmysqlclient.18.dylib ?[/quote]

I haven't used macports to install mysql, I used the "MMV MySQL Script":http://code.macminivault.com/
Do I need to create that folder in my directory structure and just copy the libmysqlclient.18.dylib there? Also, when did it become libmysqlclient.18.dylib :D Last time I checked you were still talking about libmysqlclient.dylib :S

Sorry guys, I've been looking for solutions for weeks now!

PS.: My "otool -L libqsqlmysql.dylib " looks like this:

libqsqlmysql.dylib:
libqsqlmysql.dylib (compatibility version 0.0.0, current version 0.0.0)
libmysqlclient.18.dylib (compatibility version 18.0.0, current version 18.0.0)
/usr/lib/libz.1.dylib (compatibility version 1.0.0, current version 1.2.5)
/Users/sacdallago/Qt5.2.1/5.2.1/clang_64/lib/QtSql.framework/Versions/5/QtSql (compatibility version 5.2.0, current version 5.2.1)
/Users/sacdallago/Qt5.2.1/5.2.1/clang_64/lib/QtCore.framework/Versions/5/QtCore (compatibility version 5.2.0, current version 5.2.1)
/usr/lib/libstdc++.6.dylib (compatibility version 7.0.0, current version 56.0.0)
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 169.3.0)

cdallago · wrote on 2 Apr 2014, 15:51

P.P.S.: Looking around I found the 'libmysqlclient.18.dylib' file (in the folder '/usr/local/mysql-5.6.16-osx10.7-x86_64/lib/'), and I copied it to '/opt/local/lib/mysql55/mysql/'.
This didn't solve the problem, though :(

Any other suggestions?

SGaist · wrote on 2 Apr 2014, 20:09

Hi and welcome to devnet,

The location of the library itself is not the key here. Use install_name_tool to update the path to point to your libmysqlclient.18.dylib

cdallago · wrote on 5 Apr 2014, 14:22

[quote author="SGaist" date="1396469393"]Hi and welcome to devnet,

The location of the library itself is not the key here. Use install_name_tool to update the path to point to your libmysqlclient.18.dylib[/quote]

Thanks for the suggestion SGaist! I still could't make it work after using install_name_tool, so I just switched to postgres, which worked out-of-the-box.

I will try to figure out how to make MySQL work when I won't have deadlines keeping me awake at night :S

Best regards!

SGaist · wrote on 5 Apr 2014, 20:38

Check both Qt's MySQL plugin and libmysqlclient with otool -L to ensure that everything can be found correctly

Orbotron · 2 Nov 2016, 13:31

Re: [SOLVED] QSqlDatabase: QMYSQL driver not loaded with QMYSQL driver available in OSX Mavericks

Just wanted to reply 2 years later to let people know that this solution still works on OSX if you download the offline installer qt-opensource for Mac OSX.

Thanks!

I ran otool on my libsqlmysql.dylib and it was pointing at

[dank:...clang_64/plugins/sqldrivers]$ otool -L libqsqlmysql.dylib
libqsqlmysql.dylib:
	libqsqlmysql.dylib (compatibility version 0.0.0, current version 0.0.0)
	/opt/local/lib/mysql55/mysql/libmysqlclient.18.dylib (compatibility version 18.0.0, current version 18.0.0)
	/usr/lib/libz.1.dylib (compatibility version 1.0.0, current version 1.2.5)
	@rpath/QtSql.framework/Versions/5/QtSql (compatibility version 5.5.0, current version 5.5.1)
	...

I install MySQL with Homebrew

[dank:...clang_64/plugins/sqldrivers]$ l /usr/local/lib/ | grep 18
drwxrwxr-x   32 root  admin   1.1K Feb 10 18:49 ..
drwxr-xr-x    3 dank  admin   102B Nov 18 12:35 python2.7
lrwxr-xr-x    1 dank  admin    52B Jan 29 13:11 utf8_and_gb18030.so -> ../Cellar/postgresql94/9.4.5/lib/utf8_and_gb18030.so
[dank:...clang_64/plugins/sqldrivers]$ l /usr/local/lib/ | grep mysql
lrwxr-xr-x    1 dank  admin    20B Feb  8 08:21 lib -> /usr/local/mysql/lib
lrwxr-xr-x    1 dank  admin    50B Feb  8 08:15 libmysqlclient.20.dylib -> ../Cellar/mysql/5.7.11/lib/libmysqlclient.20.dylib
lrwxr-xr-x    1 dank  admin    43B Feb  8 08:15 libmysqlclient.a -> ../Cellar/mysql/5.7.11/lib/libmysqlclient.a
lrwxr-xr-x    1 dank  admin    47B Feb  8 08:15 libmysqlclient.dylib -> ../Cellar/mysql/5.7.11/lib/libmysqlclient.dylib
lrwxr-xr-x    1 dank  admin    38B Feb  8 08:22 libmysqld-debug.a -> /usr/local/mysql/lib/libmysqld-debug.a
lrwxr-xr-x    1 dank  admin    38B Feb  8 08:15 libmysqld.a -> ../Cellar/mysql/5.7.11/lib/libmysqld.a
lrwxr-xr-x    1 dank  admin    45B Feb  8 08:15 libmysqlservices.a -> ../Cellar/mysql/5.7.11/lib/libmysqlservices.a
...

so I ran

install_name_tool -change /opt/local/lib/mysql55/mysql/libmysqlclient.18.dylib /usr/local/Cellar/mysql/5.7.11/lib/libmysqlclient.20.dylib libqsqlmysql.dylib

to double check

[dank:...clang_64/plugins/sqldrivers]$ otool -L libqsqlmysql.dylib
libqsqlmysql.dylib:
	libqsqlmysql.dylib (compatibility version 0.0.0, current version 0.0.0)
	/usr/local/Cellar/mysql/5.7.11/lib/libmysqlclient.20.dylib (compatibility version 18.0.0, current version 18.0.0)
	/usr/lib/libz.1.dylib (compatibility version 1.0.0, current version 1.2.5)
	@rpath/QtSql.framework/Versions/5/QtSql (compatibility version 5.5.0, current version 5.5.1)
	@rpath/QtCore.framework/Versions/5/QtCore (compatibility version 5.5.0, current version 5.5.1)
	/System/Library/Frameworks/DiskArbitration.framework/Versions/A/DiskArbitration (compatibility version 1.0.0, current version 1.0.0)
	/System/Library/Frameworks/IOKit.framework/Versions/A/IOKit (compatibility version 1.0.0, current version 275.0.0)
	/usr/lib/libc++.1.dylib (compatibility version 1.0.0, current version 120.0.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1213.0.0)

I feel the fact that it still says version 18.0.0 is weird but it works now for me