报错： QMYSQL driver not loaded
报错：无 QMYSQL

使用
QStringList drivers = QSqlDatabase::drivers(); //获取现在可用的数据库驱动
foreach(QString driver, drivers)
qDebug() << driver;

“QSQLITE”
“QMARIADB”
“QMYSQL”
“QMYSQL3”
“QODBC”
“QODBC3”
“QPSQL”
“QPSQL7”

解决方法：
1.安装mysql去官网下载

修改配置我的在这：D:\qt5.15\setup\5.15.2\Src\qtbase\src\plugins\sqldrivers\mysql、mysql.pro

TARGET = qsqlmysql

HEADERS += $$PWD/qsql_mysql_p.h
SOURCES += $$PWD/qsql_mysql.cpp $$PWD/main.cpp

#QMAKE_USE += mysql

OTHER_FILES += mysql.json

PLUGIN_CLASS_NAME = QMYSQLDriverPlugin
include(../qsqldriverbase.pri)

LIBS += -LD:\qt5.15\setup\mysql-8.1.0-winx64\lib -llibmysql
INCLUDEPATH += D:\qt5.15\setup\mysql-8.1.0-winx64\include
DEPENDPATH += D:\qt5.15\setup\mysql-8.1.0-winx64\include

DESTDIR=$$PWD/buidld

修改上级目录中qsqldriverbase.pri：

QT  = core core-private sql-private

# For QMAKE_USE in the parent projects.
#include($$shadowed($$PWD)/qtsqldrivers-config.pri)
include(./configure.pri)

PLUGIN_TYPE = sqldrivers
load(qt_plugin)

DEFINES += QT_NO_CAST_TO_ASCII QT_NO_CAST_FROM_ASCII

编译生成：

把它们放入：（我都放进去了，不然很烦）
D:\qt5.15\setup\5.15.2\msvc2019_64\bin
D:\qt5.15\setup\5.15.2\msvc2019_64\lib
D:\qt5.15\setup\5.15.2\msvc2019_64\plugins\sqldrivers

然后把mysql配置到环境变量里：

D:\qt5.15\setup\mysql-8.1.0-winx64\bin
D:\qt5.15\setup\mysql-8.1.0-winx64\lib