QMySql not loaded

[smb564]

First of all I must say I had spent almost two days searching a solution for this problem. I looked at a lot of forum posts regarding this and I couldn't find a solution.

When I'am using QMySql driver to access mysql database in my localhost, it says,
QMySql driver not loaded.
*But it is in the list of available drivers.

So far I have figured our there is a dependency problem in the libqsqlmysql.so (Located in /Qt/5.6/gcc_64/plugins/sqldriver/)

Here's the output when I ran the "ldd libqsqlmysql.so" command.

linux-vdso.so.1 =>  (0x00007ffeea366000)
libmysqlclient_r.so.16 => not found
libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f9d02f94000)
libcrypt.so.1 => /lib/x86_64-linux-gnu/libcrypt.so.1 (0x00007f9d02d5b000)
libnsl.so.1 => /lib/x86_64-linux-gnu/libnsl.so.1 (0x00007f9d02b41000)
libssl.so.10 => /lib/x86_64-linux-gnu/libssl.so.10 (0x00007f9d028e2000)
libcrypto.so.10 => /lib/x86_64-linux-gnu/libcrypto.so.10 (0x00007f9d02506000)
libQt5Sql.so.5 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libQt5Sql.so.5 (0x00007f9d022c2000)
libQt5Core.so.5 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libQt5Core.so.5 (0x00007f9d01bb0000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f9d01992000)
libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f9d0168e000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f9d01388000)
libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f9d01172000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f9d00dad000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f9d00ba9000)
libicui18n.so.56 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libicui18n.so.56 (0x00007f9d0070f000)
libicuuc.so.56 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libicuuc.so.56 (0x00007f9d00357000)
libicudata.so.56 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libicudata.so.56 (0x00007f9cfe974000)
libgthread-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgthread-2.0.so.0 (0x00007f9cfe772000)
librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f9cfe56a000)
libglib-2.0.so.0 => /lib/x86_64-linux-gnu/libglib-2.0.so.0 (0x00007f9cfe262000)
/lib64/ld-linux-x86-64.so.2 (0x00007f9d033bf000)
libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007f9cfe024000)

So it says libmysqlclient_r.so.16 not found.

How to fix this error?
Regards in advance.
Please help me.

[p3c0]

Hi @smb564 and Welcome,
Your system is missing mysql client libraries. Use your distro's tool to install them.
P. S. This question is quite common on this forum :)

[smb564]

@p3c0 Thank you for the reply.
I installed them.
I am using ubuntu. I have installed mysql-client & libmysqlclient-dev.
Are those the files required?

[p3c0]

@smb564 Well just the mysql client libraries unless you are recompiling the driver.
Your system probably has a different version of that library.
For eg. My system has libmysqlclient_r.so.18
Create a symbolic link of the missing library to the library installed on your system.

[smb564]

I have created a symbolic link and now the output of ldd command changed as follows.
./libqsqlmysql.so: /usr/lib/x86_64-linux-gnu/libmysqlclient_r.so.16: version `libmysqlclient_16' not found (required by ./libqsqlmysql.so)
linux-vdso.so.1 => (0x00007ffd91832000)
libmysqlclient_r.so.16 => /usr/lib/x86_64-linux-gnu/libmysqlclient_r.so.16 (0x00007f9479cce000)
libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f9479ab5000)
libcrypt.so.1 => /lib/x86_64-linux-gnu/libcrypt.so.1 (0x00007f947987c000)
libnsl.so.1 => /lib/x86_64-linux-gnu/libnsl.so.1 (0x00007f9479662000)
libssl.so.10 => /lib/x86_64-linux-gnu/libssl.so.10 (0x00007f9479403000)
libcrypto.so.10 => /lib/x86_64-linux-gnu/libcrypto.so.10 (0x00007f9479027000)
libQt5Sql.so.5 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libQt5Sql.so.5 (0x00007f9478de3000)
libQt5Core.so.5 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libQt5Core.so.5 (0x00007f94786d1000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f94784b3000)
libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f94781af000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f9477ea9000)
libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f9477c93000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f94778ce000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f94776ca000)
libicui18n.so.56 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libicui18n.so.56 (0x00007f9477230000)
libicuuc.so.56 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libicuuc.so.56 (0x00007f9476e78000)
libicudata.so.56 => /opt/Qt/5.6/gcc_64/plugins/sqldrivers/./../../lib/libicudata.so.56 (0x00007f9475495000)
libgthread-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgthread-2.0.so.0 (0x00007f9475293000)
librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f947508b000)
libglib-2.0.so.0 => /lib/x86_64-linux-gnu/libglib-2.0.so.0 (0x00007f9474d83000)
/lib64/ld-linux-x86-64.so.2 (0x00007f947a418000)
libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007f9474b45000)

[p3c0]

@smb564 Unfortunately linking is not sufficient it seems. Either you will need the exact version or you can compile the driver against the existing libraries. It is described here.

[smb564]

@p3c0 I don't know whether I am missing the obvious here. But I can't seem to find a folder like $QTDIR/qtbase/src/plugins/sqldrivers/mysql neither mysql.pro

[p3c0]

@smb564 You will need to install the source components too. The installer provides an option during installation.

[smb564]

@p3c0 Thank you very much for your help! Now it works. :)

I installed with source and followed the instructions in the Qt docs and manually built it.

[larryn46]

@smb564 I had the same problem with QMYSQL not loaded. I ran
$sudo apt-get installlibqt4-sql-mysql
and it worked