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/****************************************************************************
**
** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
**
** This file is part of an example program for Qt. This example
** program may be used, distributed and modified without limitation.
**
*****************************************************************************/
#include <qapplication.h>
#include <qsqldatabase.h>
#include <qsqlquery.h>
#include <qsqlcursor.h>
#include <qfile.h>
#define DRIVER "QPSQL7" /* see the Qt SQL documentation for a list of available drivers */
#define DATABASE "" /* the name of your database */
#define USER "" /* user name with appropriate rights */
#define PASSWORD "" /* password for USER */
#define HOST "" /* host on which the database is running */
int main( int argc, char ** argv )
{
QApplication a( argc, argv, FALSE );
QSqlDatabase * db = QSqlDatabase::addDatabase( DRIVER );
db->setDatabaseName( DATABASE );
db->setUserName( USER );
db->setPassword( PASSWORD );
db->setHostName( HOST );
if ( !db->open() ) {
qWarning( db->lastError().databaseText() );
return 1;
}
if ( argc < 2 ) {
qWarning( "Usage: %s <filename>", argv[0] );
return 1;
}
// read a file which we want to insert into the database
QFile f( argv[1] );
if ( !f.open( IO_ReadOnly ) ) {
qWarning( "Unable to open data file '%s' - exiting", argv[1] );
return 1;
}
QByteArray binaryData = f.readAll();
qWarning( "Data size: %d", binaryData.size() );
// create a table with a binary field
QSqlQuery q;
if ( !q.exec( "CREATE TABLE blobexample ( id INT PRIMARY KEY, binfield LONGBLOB )" ) ) {
qWarning( "Unable to create table - exiting" );
return 1;
}
// insert a BLOB into the table
if ( !q.prepare( "INSERT INTO blobexample ( id, binfield ) VALUES ( ?, ? )" ) ) {
qWarning( "Unable to prepare query - exiting" );
return 1;
}
q.bindValue( 0, 1 );
q.bindValue( 1, binaryData );
if ( !q.exec() ) {
qWarning( "Unable to execute prepared query - exiting" );
return 1;
}
// read the BLOB back from the database
if ( !q.exec( "SELECT id, binfield FROM blobexample" ) ) {
qWarning( "Unable to execute query - exiting" );
return 1;
}
qWarning( "\nQSqlQuery:" );
while ( q.next() ) {
qWarning( "BLOB id: %d", q.value( 0 ).toInt() );
qWarning( "BLOB size: %d", q.value( 1 ).toByteArray().size() );
}
// write another BLOB using QSqlCursor
QSqlCursor cur( "blobexample" );
QSqlRecord * r = cur.primeInsert();
r->setValue( "id", 2 );
r->setValue( "binfield", binaryData );
if ( !cur.insert() ) {
qWarning( "Unable to insert BLOB using QSqlCursor - exiting" );
return 1;
}
// read the BLOBs back using QSqlCursor
if ( !cur.select() ) {
qWarning( "Unable retrieve blobexample table using QSqlCursor - exiting" );
return 1;
}
qWarning( "\nQSqlCursor:" );
while ( cur.next() ) {
qWarning( "BLOB id: %d", cur.value( "id" ).toInt() );
qWarning( "BLOB size: %d", cur.value( "binfield" ).toByteArray().size() );
}
if ( !q.exec( "DROP TABLE blobexample" ) ) {
qWarning( "Unable to drop table - exiting" );
return 1;
}
return 0;
}
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