jdbc handling of blob type

Blob

A Blob is a JDBC interface mapping for an SQL BLOB. A Blob is obtained by the getBlob() methods of a ResultSet or CallableStatement. A Blob has methods to get its number of bytes and to determine the starting position of another Blob or an array of bytes in the current Blob. These methods work without materializing the data. To materialize the data, you can use getBinaryStream() or getBytes() ( for part or all of the Blob ) and then construct usable objects from the returned stream or byte array.

For Blob storage use setBlob() from a PreparedStatement or updateObject from an updatable ResultSet. Again, this is where most discussions end, with the example retrieving a Blob from one row and putting it to another row in the same or a different table.

How does Blob data get there in the first place? Again, look at the Blob methods, this time getBinaryStream() and getBytes(): use PreparedStatement's setBinaryStream() or setBytes() methods to populate the Blob.