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    <p>Take a look at this question answer: <a href="https://stackoverflow.com/q/3124244/209899">How to stores and Pictures in Db40?</a></p> <p>I repost my answer again, a bit updated with the links to the Java documentation:</p> <p>There are <a href="http://developer.db4o.com/Documentation/Reference/db4o-8.0/java/reference/Content/implementation_strategies/type_handling/blobs.htm" rel="nofollow noreferrer">two basic ways</a> to handle Blobs. Either you store a blob as byte-array in the database or you use the special db4o-Blob-Type. Both have their advantages.</p> <p><strong>Advantages/Disadvantages with byte array:</strong></p> <ul> <li>The blobs are in the db4o-database-file. So there's only a single file to copy around.</li> <li>Byte-arrays are part of the normal db4o-transaction and behave as expected.</li> <li>When storing large blobs, you might run into the <a href="http://developer.db4o.com/Documentation/Reference/db4o-8.0/java/reference/Content/tuning/performance_hints/increasing_the_maximum_database_file_size.htm" rel="nofollow noreferrer">database-size limitation of db4o</a>. (256 GB)</li> </ul> <p><strong>Advantages/Disadvantaged with db4o-blobs</strong></p> <ul> <li>The blobs are stored as regular files outside the database. This keeps the database itself small. Furthermore you just can access all stored blobs with a regular application.</li> <li>You always need to copy the blob-directory and the database.</li> <li>The db4o-blobs works outside the db4o transaction. This means that a db4o-blob behaves different than any other stored object (and the API is a little strange). However this allows to retrieve a db4o-blob without blocking the current transaction.</li> </ul> <p>For your case I would store a byte[] array with the picture in the Person class. Or you create a special Image-class. This image-class contains then a byte-array with the picture. And a few methods to convert this byte-array from and to a Winforms-bitmap.</p>
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