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

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'''English''' [[How to Store and Retrieve an Image or File with SQLite Spanish|Español]] [[How to Store and Retrieve Image on SQLite Bulgarian|Български]]
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'''English''' [[How_to_Store_and_Retrieve_an_Image_or_File_with_SQLite_Spanish|Español]] [[How_to_Store_and_Retrieve_Image_on_SQLite_Bulgarian|Български]]<br />[[Category:HowTo]]<br />[[Category:snippets]]
  
=How to Store and Retrieve an Image or File with <span class="caps">SQL</span>ite=
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= 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:
 
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.<br /> 2. Store QByteArray as a Binary Large Object in database.
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1. Read the system file into a QByteArray.<br />2. Store QByteArray as a Binary Large Object in database.
  
 
For example :
 
For example :
  
Now, the image/file can be retrieved like any other data<br />
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<code><br /> QFile file&amp;amp;#40;fileName&amp;amp;#41;;<br /> if (!file.open(QIODevice::ReadOnly)) return;<br /> QByteArray byteArray = file.readAll();
  
Creating a QPixmap from QByteArray :<br />
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QSqlQuery query;<br /> query.prepare(&quot;INSERT INTO imgtable (imgdata) VALUES (?)&quot;);<br /> query.addBindValue(byteArray);<br /> query.exec&amp;amp;#40;&amp;#41;;<br /></code>
  
It is done. Now the pixmap can be used in a Button as icon or in label etc.
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Now, the image/file can be retrieved like any other data<br /><code><br /> QSqlQuery query(&quot;SELECT imgdata FROM imgtable&amp;quot;);<br /> query.next();<br /> QByteArray array = query.value(0).toByteArray();<br /></code>
  
===Categories:===
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Creating a QPixmap from QByteArray :<br /><code><br /> QPixmap pixmap = QPixmap();<br /> pixmap.loadFromData(array);<br /></code>
  
* [[:Category:HowTo|HowTo]]
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It is done. Now the pixmap can be used in a Button as icon or in label etc.
* [[:Category:snippets|snippets]]
 

Revision as of 14:45, 23 February 2015

English 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 :

<br /> QFile file&amp;amp;#40;fileName&amp;amp;#41;;<br /> if (!file.open(QIODevice::ReadOnly)) return;<br /> QByteArray byteArray = file.readAll();

QSqlQuery query;<br /> query.prepare(&quot;INSERT INTO imgtable (imgdata) VALUES (?)&quot;);<br /> query.addBindValue(byteArray);<br /> query.exec&amp;amp;#40;&amp;#41;;<br />
Now, the image/file can be retrieved like any other data
<br /> QSqlQuery query(&quot;SELECT imgdata FROM imgtable&amp;quot;);<br /> query.next();<br /> QByteArray array = query.value(0).toByteArray();<br />
Creating a QPixmap from QByteArray :
<br /> QPixmap pixmap = QPixmap();<br /> pixmap.loadFromData(array);<br />

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