Problems while storing a BLOB

Question

Hi
I need to store a blob in a MS Access db while receiving a mail, but I can't arrive!
This is my code, could anyone help me?
Many thanks in advance.
                         Blob blob = null;
                         PreparedStatement pst2 = con.prepareStatement("INSERT INTO TMail (Allegato, NomeAllegato) VALUES (?, ?)");
                         pst2.setBlob(1, blob);
                         pst2.setString(2, "prova");
                         pst2.executeUpdate();
                         con.commit();
                         PreparedStatement dbQuery = con.prepareStatement("SELECT Allegato " +
                                   "FROM TMail WHERE NomeAllegato = " + "'prova'"); //primaryKey);
               ResultSet rs = dbQuery.executeQuery();
               rs.next();
               blob = rs.getBlob("Allegato");
               OutputStream outstream = blob.setBinaryStream(1L);
                long size = blob.length(); // sarebbe getBufferSize()
                byte[] buffer1 = new byte[(int)size]; // occhio al cast!
                int length = -1;
                while((length = in.read(buffer1)) != -1)
                         outstream.write(buffer1, 0, length);
                outstream.close();
                PreparedStatement pst1 = con.prepareStatement("INSERT INTO TMail (Allegato) VALUES (?)");
                 pst1.setBlob(1, blob);
                 pst1.executeUpdate();
                 con.commit();
                 ... then I'm uploading the others fileds into a db.Maybe is possible to store the blob withut to reserve an empty space while uploading the others fields?

Answer 1

This post will not solve your problem.
However, MS Access IS NOT a database, it is an
application that mimics relational databasebehavior,
but a database it is not. There are formal definitions of databases and at
least to some extent MS Access meets the definition.I believe at to be a true database, you must provide for multiple users to access the db via network protocols, independent of the OS. Access doesnt do that. JMO.
>
Secondly, whenever I tried
to use MS Access and Java via the JDBC-ODBC Bridge
during my college career, I had nothing butproblems.
And which of the following did you have problems
with?
1. The ODBC driver itself?
2. Understanding what the bridge, the MS Access ODBC
driver and what MS Access allows?
3. Something else that has nothing to with MS Access
but instead might apply to any database?
Most of our problems were related to the JDBC-ODBC bridge and the underlying system DSN. We also had numerous problems after executing even the simplest of select querries, we would end up with empty result sets. Once we switched to MySQL and the Connector/J, the problems went away.
Another problem was the schools policy of not allowing us to save data on any computer. We could install software and save files, but as soon as the 'puter was turned off, the HDD was restored to the original image 'approved' by the school. For our senior capstone courses we were susposed to design, develop, and deploy a system to solve some problem. We were free to choose the topic. Given the computer policy it was a waste of time unless you used Microsoft Access. We couldnt even save DSN's on the schools puters nor change the time of the system.
Further, I did some research on the web and the
prevailing view I discovered was not to use MS
Access.I believe you will find many more opinions that you
shouldn't be using java but instead should be using
C# or C++.
So what language do you program in?Java 2 SE
>
hope you find a solution to your problem. In
addition, a small piece of advice for you in the
future would be to use MySQL (you can downloadfree)
and or Oracle 10g (also a free download). Presumably you are addressing the needs of a student,
because a business can not use Oracle for free. Even
a minimal install is quite expensive.Yes, I assumed this was a student project as the OP mentioned something about a test/project.
I am also guessing the OP's school is heavily vested with Microsoft's products such as the Office suite, Visual Studio, and even the class registration web sit did not function correctly without IE5 or better. I normally use Firefox and I always had to register using IE.
>
And I haven't checked recently but at one time that
was potentially true for MySQL as well.I believe MySQL uses a dual licensing model. If you develop a GPL open source application, its free. If you release some comercial product that uses MySQL, you must buy a license.
Most of the time I am using the DB's at home for educational / proof of concept type stuff. For school projects. I do not believe there is any problem. However, if the project is soo good that it can be comercially used, then by all means buy a license.
>
Both also require installs (of the database itself)
into the production environment. MS Access on a
windows box does not require that.
I dont understand what you are saying. MySQL runs fine on my laptop. Also whats to prevent a company from deploying to a test / development environment prior to roll out? Other than money that is.
Those are
both true databases. Please before anyone screams
at me about database X or Y... I know there are a
myriad of others out there but Oracle and MySQLare
the 2 biggest dogs out there competing with
Microsoft.
>
The competition with those would be MS SQL Server and
not MS Access. And MS SQL Server also is "free" at
least in the same way that Oracle is.Thats cool. The last time I had looked all the SQL server downloads were time limited to like 90 days. But that was several years ago.