BLOB insert behavior with thin driver using standard JDBC2.0 and ORACLE-JDBC2.0API

Question

We have a problem with a BLOB insert to an oracle 8.1.7 DB using Oracle 8.1.7 JDBC thin driver.We get socket read/write error after inserting 32k of data using the standard JDBC2.0 API but using the Oracle JDBC2.0API (using OracleResultSet) it goes fine. We have a requirement to use the standard JDBC2.0 so that our code works with multiple database vendors. Is there another way to get in the blob data with standard JDBC API & using thin driver...?
thanks,
Madhu
Here is my sample test program that does both standard & oracle specific JDBC Blob test insert.
import java.sql.*;
import java.io.*;
import oracle.sql.BLOB;
import oracle.jdbc.driver.OracleResultSet;
public class testBLOB {
//trying to insert a huge file to a BLOB
static String fileName = "/kernel/genunix";
public static void main(String[] args) {
String driverName = "oracle.jdbc.driver.OracleDriver";
String dbURL = "jdbc:oracle:thin:@localhost:1521:test"; //thin driver
String user = "BlobTest";
String passwd = "BlobTest";
Connection con=null;
try {
Class.forName(driverName);
con=DriverManager.getConnection(dbURL, user,passwd);
catch (Exception e) {
e.printStackTrace();
close(con);
int i = 0;
while (i < args.length) {
if (args.equals("-f"))
fileName = args[++i];
i++;
System.out.println("The file being Stored is: "+fileName);
createTable(con);
insertUsingOracleAPI(con);
insertUsingJDBC20API(con);
//readDB(con);
static String getFileName() {
return fileName;
public static void close(Connection con) {
try {
if (con != null) {
con.close();
catch (Exception e) {
System.exit(-1);
public static void createTable(Connection con) {
Statement stmt ;
try {
stmt = con.createStatement();
stmt.execute("DROP TABLE basic_blob_table");
stmt.close();
catch (SQLException sqlEx) {
System.out.println("Dropped the Table");
try {
stmt = con.createStatement();
stmt.execute("CREATE TABLE basic_blob_table ( x varchar2(30), b blob)");
stmt.close();
catch (SQLException sqlEx) {
sqlEx.printStackTrace();
close(con);
System.out.println("Created the Table");
public static void insertUsingOracleAPI(Connection con) {
OutputStream os = null;
Statement stmt = null;
ResultSet rs = null;
FileInputStream is = null;
try {
con.setAutoCommit(false);
stmt = con.createStatement();
stmt.execute("INSERT INTO basic_blob_table VALUES( 'OracleAPI', empty_blob())");
System.out.println("Inserted the dummy Row");
rs = stmt.executeQuery("Select * from basic_blob_table where x='OracleAPI'");
if (rs != null && rs.next()) {
BLOB blob = ((OracleResultSet)rs).getBLOB(2);
File file = new File(getFileName());
is = new FileInputStream(file);
os = blob.getBinaryOutputStream();
byte[] chunk = new byte[1024];
int length = -1;
while((length = is.read(chunk)) != -1)
os.write(chunk, 0,length);
System.out.println("Inserted the File " + getFileName() );
catch (Exception e) {
e.printStackTrace();
finally {
try {
if (os != null) {
os.flush();
os.close();
if (is != null)
is.close();
stmt.close();
con.commit();
con.setAutoCommit(true);
catch (Exception e) {}
public static void insertUsingJDBC20API(Connection con) {
PreparedStatement stmt = null;
FileInputStream is = null;
try {
stmt = con.prepareStatement("INSERT INTO basic_blob_table VALUES(?,?)");
File file = new File(getFileName());
is = new FileInputStream(file);
stmt.setString(1,"JDBC20API");
stmt.setBinaryStream(2,is,(int)file.length());
stmt.executeUpdate();
catch (Exception e) {
e.printStackTrace();
finally {
try {
if (is != null)
is.close();
stmt.close();
catch (Exception e) {}
null

Answer 1

Thanks for the response.
I understand what you are saying...
that readers don't block writers in Oracle (the same is true in SQL Server 2000).
However, I don't see how my test case is working correctly with Oracle (the exact same code acting as I'm thinking it should with SQL Server, but I still think it is acting incorrectly with Oracle).
I have transaction A do this:
update <table> set <column2>=<value> where <column1>='1'
then I use Thread.sleep() to make that program hang around for a few minutes.
Meanwhile I sneak off and start another program which begins transaction B. I have transaction B do this:
select * from <table> where <column1>='1'
and the read works immediately (no blocking... just as you have said) however, transaction A is still sleeping, it has not called commit() or rollback() yet.
So what if transaction A were to call rollback(), the value read by transaction B would be incorrect wouldn't it ?
Both A and B use setAutoCommit(false) to start their transactions, and then call setTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED).
Isn't that supposed to guarantee that a reader can only read what is committed ?
And if a row is in "flux"... in the process of having one or more values changed, then the database cannot say what the value will be ?
I can almost see what you are saying.
In letting the reader have what it wants without making it wait, I suppose it could be said that Oracle is holding true to the "only let committed data be read"
So if that's it, then what if I want the blocking ?
I want an entire row to be locked until whoever it in the middle of updating, adding, or removing it has finished.
Do you know if that can be done with Oracle ? And how ?
Thanks again for helping me.