How to Store and Retrieve Image on SQLite

This article may require cleanup to meet the Qt Wiki's quality standards. Reason: Auto-imported from ExpressionEngine. Please improve this article if you can. Remove the {{cleanup}} tag and add this page to Updated pages list after it's clean.

English | Deutsch | Español | Български

How to Store and Retrieve an Image or File with SQLite

Images or any files can be stored in a database. Here is one way to do it using the following steps:

1. Read the system file into a QByteArray. 2. Store QByteArray as a Binary Large Object in database.

For example :

 QFile file(fileName);
 if (!file.open(QIODevice::ReadOnly)) return;
 QByteArray byteArray = file.readAll();

QSqlQuery query;
 query.prepare("INSERT INTO imgtable (imgdata) VALUES (?)");
 query.addBindValue(byteArray);
 query.exec();

Now, the image/file can be retrieved like any other data

 QSqlQuery query("SELECT imgdata FROM imgtable");
 query.next();
 QByteArray array = query.value(0).toByteArray();

Creating a QPixmap from QByteArray :

 QPixmap pixmap = QPixmap();
 pixmap.loadFromData(array);

It is done. Now the pixmap can be used in a Button as icon or in label etc.