Qt 连接 mysql 报错 QSqlDatabase: MYSQL driver not loaded

参考： 

https://blog.csdn.net/o___GRoot/article/details/111320313 

https://blog.csdn.net/sksukai/article/details/105344308

我的解决步骤：

1. 指定qmake 

qmake: could not exec ‘/usr/lib/x86_64-linux-gnu/qt4/bin/qmake’: No such file or directory

需要修改如下文件内容
/usr/lib/x86_64-linux-gnu/qt-default/qtchooser/default.conf
从

/usr/lib/x86_64-linux-gnu/qt4/bin
/usr/lib/x86_64-linux-gnu

修改为

/home/mike/Qt5.9.7/5.9.7/gcc_64/bin
/usr/lib/x86_64-linux-gnu/qt4/bin
/usr/lib/x86_64-linux-gnu

即指定qt安装目录下的qmake。

2. 编译源码

执行如下命令：

cd ~/Qt5.9.7/5.9.7/Src/qtbase/src/plugins/sqldrivers
sudo qmake -- MYSQL_PREFIX=/usr/local
cd mysql/
sudo qmake "INCLUDEPATH+=/usr/include/mysql" "LIBS+=-L/usr/lib/x86_64-linux-gnu"
sudo make
sudo make install

完毕。