![]() ![]() Inserting BLOBs should be done using either a prepared query where the BLOBs are bound to placeholders or QSqlTableModel, which uses a prepared query to do this internally. You should use a forward only query to select LOB fields (see QSqlQuery::setForwardOnly()). OCI BLOB/LOB Supportīinary Large Objects (BLOBs) can be read and written, but be aware that this process may require a lot of memory. Leave the username and password empty when opening a connection with QSqlDatabase to use the external credentials authentication. Usually, this means that the database server will use the user authentication provided by the operating system instead of its own authentication mechanism. The Qt OCI plugin supports authentication using external credentials (OCI_CRED_EXT). This requires that the database SID is passed to the driver as the database name, and that a hostname is given. It's possible to connect to a Oracle database without a tnsnames.ora file. The plugin will auto-detect the database version and enable features accordingly. This is dependent on what Oracle indicates it supports. The Qt OCI plugin supports connecting to Oracle database as determined by the version of the instant client used. libmysql.dll additionally needs the MSVC runtime libraries which can be installed with vcredist.exe QOCI for the Oracle Call Interface (OCI) It must be placed in the same folder as the application executable. When you distribute your application, remember to include libmysql.dll / libmariadb.dll in your installation package. Qt -cmake -G Ninja \Src\qtbase\src\plugins\sqldrivers -DCMAKE_INSTALL_PREFIX = \ -DMySQL_INCLUDE_DIR = "C:\mysql-8.0.22-win圆4\include" -DMySQL_LIBRARY = "C:\mysql-8.0.22-win圆4\lib\libmysql.lib" Tell qt-cmake where to find the MySQL / MariaDB header files and shared libraries (here it is assumed that MySQL / MariaDB is installed in /usr/local) and build: Depending on your Linux distribution, you may need to install a package which is usually called "mysql-devel" or "mariadb-devel". You need the MySQL / MariaDB header files, as well as the shared library libmysqlclient. How to Build the QMYSQL Plugin on Unix and macOS Please refer to the MySQL documentation, chapter "libmysqld, the Embedded MySQL Server Library" for more information about the MySQL embedded server. This can be done by adding -DMySQL_LIBRARY=libmysqld. To use the embedded MySQL server, simply link the Qt plugin to libmysqld instead of libmysqlclient. With the embedded MySQL server, a MySQL server is not required to use MySQL functionality. The MySQL embedded server is a drop-in replacement for the normal client library. Note: and are variables local to the current connection and will not be affected by queries sent from another host or connection. ![]() For example, you can do this as follows, to locate MySQL: this is required for PostgreSQL and SQLite). You should prefer this method if module needs to set properties for the provided target libraries (e.g. ![]() In some cases it's more convenient to use CMAKE_INCLUDE_PATH and CMAKE_LIBRARY_PATH variables to locate required libraries. This is especially useful if the package provides its own set of system libraries that should not be recognized by the build routine. When you configure drivers in the manner described above, CMake skips any dependency checks and uses the provided paths as is. ![]()
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