MySQL Dual Connection

MySQL Dual Connection is an example of how to achieve a dual (server & embedded) connection to MySQL/MariaDB in one Qt 5 application. The example creates a new Qt SQL driver (embeddedDriver) that can be used with the rest of Qt SQL classes.

Special requirement

• Uses libmysqld.a (MySQL/MariaDB embedded library). It does not work with libmysqld.so because Qt 5 would not be able to determine which library to use “mysqlclient” (server libary) or “mysqld” at run time.
• Requires a MySQL/MariaDB “share” directory that matches the library version. At this point the “share” directory inside the example database (embdbtest) matches MariaDB 10.0.19.

Parameters

• a - Path to the embedded database.
• d - Schema name.
• r - Use remote connection. False by default.
• H - MySQL/MariaDB host. Default is localhost.
• P - MySQL/MariaDB port. Default is 3306.
• u - MySQL/MariaDB user name.
• p - MySQL/MariaDB user password.

Example of embedded connection

$ ./mysqldualconnection -a /path_to_my_embedded_database -d my_embedded_database

Example of server connection

$ ./mysqldualconnection -r -H my_MariaDB_server -u my_user_name -p my_password -d my_embedded_database

Technology

ODK Tools was built using:

• C++, a general-purpose programming language.
• Qt 5, a cross-platform application framework.
• CMake, a cross-platform free and open-source software for managing the build process of software using a compiler-independent method.

Building and testing

To build this site for local viewing or development:

$ git clone https://github.com/qlands/mysqldualconnection.git
$ cd mysqldualconnection
$ mkdir build
$ cbuild
$ cmake ..
$ ./mysqldualconnection -a ../embdbtest -d embtest
>> Embedded connection
>> Code: 2 - Description: Row 2
>> Code: 1 - Description: Row 1

Author

Carlos Quiros (cquiros_at_qlands.com)

License

This repository contains the code of:

• Qt 5 which is licensed under the LGPL v2.1 and GPL v 3.0 licenses.

Otherwise, the contents of this application is GPL V3.