Difference between revisions of "How to Store and Retrieve Image on SQLite"

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(Cleanup)
(various minor fixes)
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{{LangSwitch}}
 
{{LangSwitch}}
[[Category:snippets]]
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[[Category:HowTo]]
 
 
Images or any files can be stored in a database. Here is one way to do it using the following steps:
 
Images or any files can be stored in a database. Here is one way to do it using the following steps:
  
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# Store QByteArray as a Binary Large Object in database.
 
# Store QByteArray as a Binary Large Object in database.
  
For example :
+
For example:
  
 
<code>
 
<code>
QFile file(fileName);
+
QFile file(fileName);
if (!file.open(QIODevice::ReadOnly)) return;
+
if (!file.open(QIODevice::ReadOnly)) return;
QByteArray byteArray = file.readAll();
+
QByteArray byteArray = file.readAll();
  
 
QSqlQuery query;
 
QSqlQuery query;
query.prepare("INSERT INTO imgtable (imgdata) VALUES (?)");
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query.prepare("INSERT INTO imgtable (imgdata) VALUES (?)");
query.addBindValue(byteArray);
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query.addBindValue(byteArray);
query.exec();
+
query.exec();
 
</code>
 
</code>
  
 
Now, the image/file can be retrieved like any other data
 
Now, the image/file can be retrieved like any other data
 
<code>
 
<code>
QSqlQuery query("SELECT imgdata FROM imgtable");
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QSqlQuery query("SELECT imgdata FROM imgtable");
query.next();
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query.next();
QByteArray array = query.value(0).toByteArray();
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QByteArray array = query.value(0).toByteArray();
 
</code>
 
</code>
  
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</code>
 
</code>
  
It is done. Now the pixmap can be used in a Button as icon or in label etc.
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It is done. Now the pixmap can be used in a {{class|QPushButton}} as icon or in label etc.
 +
 
 +
[[Category:Snippets]]
 +
[[Category:HowTo]]

Revision as of 15:34, 16 November 2015

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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 QPushButton as icon or in label etc.