I have an entity with a lob value:
@Lob
public byte[] getData() {
return data;
}
I have a large amount of data that Iretrieve in small parts from the database, convert it to xml and stream it to the blobfield.
public void insertData() throws Exception {
Context ctx = new InitialContext();
DataSource ds = (DataSource) ctx.lookup("java:/UdtraekDS");
Connection connection = ds.getConnection();
try {
if (connection != null) {
String readStatementBlobStreamOracle = "select data from as_udtraek where name = ? for update";
String readStatementBlobStreamSQLServer = "select data from as_udtraek (UPDLOCK) where name = ?";
// Select sql depends on the database
String sql = Util.isOracle() ? readStatementBlobStreamOracle : readStatementBlobStreamSQLServer;
PreparedStatement ps = connection.prepareStatement(sql);
ps.setString(1, "allekatalogydelser.xml");
ResultSet res = ps.executeQuery();
if (res.next()) {
Blob val = res.getBlob(1);
OutputStream outputStream = val.setBinaryStream(1);
logger.info("Writing data to blob");
// Lots of data will be generated here and written to the outputstream
// For test
outputStream.write("testing".getBytes());
outputStream.flush();
outputStream.close();
}
res.close();
ps.close();
}
} catch (Exception e) {
logger.error(1, e);
} finally {
try {
connection.close();
} catch (SQLException e) {
logger.warn("could not close the connection", e);
}
}
}
In the example above I retrieve the existing AS_UDTRAEK entity with the name "allekatalogydelser.xml? and write the text ?testing? to the blobfield. This works perfectly well with an oracle db but with a Microsoft SQL server 9 no data is written to the blob and no exception is thrown.
Can anyone tell me what I'm doing wrong.
